NetworkToolbox news

A few words about KRACK

You will have heard about the KRACK (Key Reinstallation Attacks) vulnerability. I think all information (even – as usual – some over hyped and misinterpreted) is available from many sources. If you are interested, I would recommend reading Mathy Vanhoef’s information on his website

However, here is a summary:

  • The WPA2 WiFi encryption has a weakness that can be used to sniff network traffic
  • Your WPA2 password can not be discovered by this attack, however it is not necessary for sniffing the traffic by using this attack
  • Almost all routers and WiFi Network devices are affected (including iPhones and iPads using the current iOS Versions)
  • This vulnerability can (only) be fixed with updates on both ends, Router AND Client

What to do:

  • Look for updates (for your Router AND your Clients). Throw away devices that can’t be updated.
  • Until updates are installed, prevent using sensitive information (e.g. Banking) on any WiFi device. Better use cabled devices for this.
  • If you really have to, double check if you are indeed using HTTPS while submitting sensitive information. Man-in-the-middle attacks, which are possible by using this vulnerability, will most of the time cause HTTPS connections to end up as HTTP connections in order to capture the traffic.
  • Carefully look out for unusual logins on your accounts or anything else unusual. In doubt, change passwords for accounts using cabled devices.
  • After everything calms down, take this opportunity to change all your passwords

Don’t trust the evil,




NetworkToolbox news

Next update 11.0.3 now available – UPDATE 2

After finishing and submitting my Update, I contacted Apple and asked for an Expedite review. Within one hour, Apple reviewed and released the App.

This was probably world record. A big thank you to Apple!


Unfortunately, there was a bug in the UPnP Scanning engine which was causing the App to crash when there is a ‘misbehaving’ UPnP device.

As this happened in the UPnP Scanning engine which is also used for the new Advanced Scanning feature, the new feature wasn’t working for some of you.

I hope that the new update will now work for you as expected.

To locate and fix this bug, it was very helpful that some of you enabled Crash-log submission in the Settings ( iOS Settings -> Privacy -> Analytics -> enable: Share Analytics as well as Share with App Developer). This way, I was receiving the anonymous crashlog via Apple and was able to analyze the cause. Thank you!

Have a great weekend (at least I will have one now as the update is out),



UPDATE Sunday 1st Oct:

In case some of you are wondering about the availability of the update, Apple currently has major outages. They maintained some of their servers yesterday, now claim that everything should be up and running but that obviously is not the case. Some support websites are not available and other Apple websites have wrong contents. So much to Apples world record of releasing Network Toolbox.

UPDATE Monday 2nd Oct:

Finally, the new update seems to be available after almost two days.

Thanks for your patience.



NetworkToolbox news

Version 11 of NetworkToolbox will be available Thursday!

Good news though. The new update will be available Thursday, September the 28th!

I have just updated the manual. For instance the chapters for Network Scanning and the new tools like Whois, DNS and UPnP. So if you want to see what’s coming, just have a look to these manual chapters.

This is, what has been changed:


► New WhoIs Lookup Tool (see details about any domain and who has registered it)
► New DNS Tool (query ANY! DNS Server for domains, see records and response times)
► New visual Traceroute (see trace routes on a map)
► New UPnP Tool (see which UPnP devices are noisy on your network)


► Extensive improvements of the Network Scanning engine
► Improved Morpheus Map
► Improved Bonjour Browser
► Terminal and SSH support for Backspace and CR/LF

Bug Fixes:

► Fixed Crash in External Apps Tool
► Special Keyboard Bar are now visible, no longer transparent
► Display of wrong MAC Addresses fixed
► Bug in MAC Database fixed which caused some Vendors not to be found
► Fixed bug in traversal test or Password test where entries, already tried were not marked accordingly

As always, this version was again a challenge. Please note, with iOS 11 MAC Addresses can no longer be displayed as the API has been removed by Apple for privacy reasons. However, the vastly improved scanning engine now combines many other information available about any IP Address on your network. This not just compensates the missing MAC address. Now you can see as much information as discoverable in one single place. Network scanning was never easier and more convenient before.

As this was again a major update with several weeks of development time, please consider to rate my App to keep it rolling.

In case you may find any bug, please let me know, I want to fix it!

Thank YOU!


NetworkToolbox news

☛ NetworkToolbox, iOS 11 and MAC Addresses

Last time, when iOS 10.2 has been introduced, the ability for NetworkToolbox to show MAC Addresses was no longer available as Apple has removed access to MAC Addresses due to security concerns and to increase our privacy. (see MAC Addresses are back)

It was a real challenge to find a workaround to be able to show the MAC Address again. My solution still works under iOS 10.3.3.

Now, with iOS 11 knocking at the door, you may wonder if it will still work. The answer is no. Unfortunately. Apple made my workaround unusable again in iOS 11.

I already investigated into this again for several days (and nights) but it seems, this time, Apple did a great job. They even fixed some additional (severe) security issues I found last time while I was looking for an alternative to get the MAC Address.

However, the consequence of this on iOS 11 is now, not only the lack of the ability to show the MAC address. The main disadvantage is, that I no longer can display the device Vendor, which is derived from the MAC Address using the internal MAC Database. This is and was a very valuable information while scanning a local network as it often helps to identify a device. Unfortunately, this is gone now.

I spoke to two Apple employees. Both told me, that Apple wants to protect users against Developers who misuse the MAC Address to track user activities and they said that this has precedence over the missing feature for my App.

I told them that this is a very good approach with good intentions but even without a MAC Address there are a couple of (even easier) ways to track user activities and, depending on the setup, a MAC Address can even be derived from IPv6 Address and that there isn’t much Apple can do against it.

I also recommended to add a security setting which could be used to allow/disable MAC Address access similar to camera or microphone access. So users can decide which App should be allowed to have access to the MAC Address.

One of these Apple employees told me that he is using my App quite often and found my statements and suggestions quite reasonable.

I am not sure (I even doubt) that my conversation with Apple will change the situation but maybe if more people (like you) would let Apple know, maybe it will.

Nevertheless, here are the plans for my next steps:

  • Shortly after iOS 11 has been released, I will create another Update of NetworkToolbox

(Shortly ‘after’ because I want to create an update based on and for the final iOS 11 version which makes sense as the App already runs just fine on iOS 11 (except for the MAC Address) and thus, wouldn’t require an immediate update)

  • I will give the MAC Address issue another (short!) try but will not waste too much time. Instead, I will polish the Network Scanning tool that it will provide as much usability as possible even without a MAC Address
  • Finally and in addition, that next update will include things, I already worked on (most of them have already been finished).


Thanks for your suggestions, which helped to make this App even better.

Stay tuned,



NetworkToolbox news

To Petya or NotPetya

You will have heard about the recent attack to Windows PCs called Petya or NotPetya.

The reason why some people say NotPetya is, that it is not a new version of the former Petya malware, even though it looks so.

This one is again (like WannaCry) based on the recently released NSA Tools (see my related post here).

But it is worse than WannaCry and was just built to create chaos and damage on as many systems as possible. The current damage is already massive. I bet you will hear more about it during the next days.

I will not repeat all the rumors about the source or intentions here.

Here is just, what I have done and what you should do (sorry, I should rather say “have to do”):

  • BACKUP BACKUP BACKUP (everything you don’t want to loose, your Pictures, Movies, Documents, Source-code, Letters, Tax Statements, Banking Documents etc.)
  • UPDATE UPDATE UPDATE (everything PCs, Routers, NASes, Mobile Devices)
  • Replace or switch off your Windows XP PCs
  • Do this on every Windows PC:
    • Start a command prompt with admin rights (right click on the Windows Icon in the lower left corner and select ‘Command Prompt (Admin)’
    • And type:

These commands will create three files perf, perfc.dll and perfc.dat and will mark them read only. The current version of NotPetya will stop working if these files were found. This is a very simple thing and most likely, a new version of NotPetya will disregard these files. However it doesn’t hurt and has no other side effect.

Finally, if you are already infected, for instance if you see a sudden Checkdisk message trying to repair your hard-drive or anything else unusual:

  • Immediately switch off your PC (even if Checkdisk says you should not)
  • Disconnect your PC from your network
  • Try to boot it stand alone. If this doesn’t work anymore, most likely, your data is lost.
  • Switch off your router / disconnect from the Internet
  • Check your other PCs as you might have a chance that they are not yet infected.

Don’t trust the evil.



NetworkToolbox news

NSA Tools available to everybody – Update your PCs. Quick!

As you may have heard, a Group called Shadowbrokers have stolen Hacking tools from the NSA and made them available to the public.

I had a chance to take a look at these tools. A few days ago they already released some tools but those tools were quite outdated and not really harmful if you don’t use an old Windows XP or Vista PC. But these new tools are indeed up-to-date and I was able to use the tools to compromise one of my Windows 10 PCs which hasn’t been updated for a few days. After it was updated with the latest Creators Update from Microsoft including all security updates, that was no longer possible.

The NSA Tools also include tools to disable or hide themselves against all known virus scanners, including Microsoft.

There are rumors that NSA has informed Microsoft about the fact that their tools were stolen along with information about the vulnerabilities these tools are using so Microsoft was able to fix these vulnerabilities. This makes sense as these vulnerabilities are existing for quite some time now and it is interesting that Microsoft has created these fixes before Shadowbrokers have released the Tools to the public.

About the NSA tools

Some people already asked if these hacking tools are indeed from the NSA or ‘just’ from Hackers. I have seen many similar tools by many developers and of course developed my own. The available tools have been developed in Java, Python and Perl, some are available as binaries.

Even though I found some humor like in the Zippybeer tool which contains an ASCII image like this:

I found the code really really well organized and straight forward. Typical hacker code contain typos, they often don’t really care about code quality and a lot of code I have seen looks really ‘messy’ or even contains messages to other hackers. This code looks excellent, very reliable and foolproof with a lot of try/catch and exception handling to ensure that the tools are doing what they are supposed to do or fail and let the user know why and not leaving a trace. This code hasn’t been developed in a rush and it is indeed professional, just like a commercial software. This is why I am pretty sure that it comes from the NSA.

What you need to do

So if you didn’t already, hurry and update your Windows PCs. If you are using older Windows Versions than Windows 10, disconnect them from the internet.

This is not because of the NSA as they may have already (or soon) finished new tools which will still be able to compromise your PC. This is mainly because these NSA tools are now available to the public. They are easy to use and I suspect not only by people with good intentions.

Don’t trust the evil.

Happy Easter.


NetworkToolbox news

Major CloudFlare data leak on millions of Websites – and Apps

CloudFlareNormally, you may find your stolen Email addresses and sometimes even stolen passwords in wrong hands because a certain website has been individually compromised – like happened with Adobe, DropBox or Yahoo recently.

Even though the Yahoo breach with more than 500 million affected user accounts sound like a major breach, a recent CloudFlare data leak has a new dimension.

CloudFlare is a service, used by millions of websites, to improve availability and speed. CloudFlare servers are working between the visitor of a website and the website itself and can be seen as a kind of cache.

What happened was, that since September 22nd 2016 and February the 18th 2017, CloudFlare had a bug which resulted in CloudFlare to respond back to the website visitor with memory contents of the CloudFlare servers instead of the contents of the visited website.

These memory contents often contain sensitive data of other websites such as API Keys, security tokens or even internal server and database passwords. Not only that this data may contain your personal data, even worse, with this information, the effected website and database can be compromised.

Things got worse as this leaked content has already been indexed by Search Engines like Google over the past Months. The issue with this is, that the data is now (still) available to everybody and can easily be found by using special Search terms. Google and other Search Engines are working on deleting such contents but it will be almost impossible to get rid of all leaked data.

Nick Sweeting provides a zipped list of sites (so far, he found more than 4 million sites) that are using CloudFlare which might be affected by this leak.

Not only Websites but also Apps (iOS and Android) such as FitBit and Uber are affected as they also use CloudFlare for data exchange. Data of such Apps have also been found by searching Google.

So what can you do?

Not much to be honest but you can take this as a gentle reminder to:

  • Change passwords frequently
  • Don’t use one and the same password for different services
  • Use fake accounts and fake Email addresses for registration wherever possible
  • Don’t trust the evil

Best regards,


NetworkToolbox news

Online shopping risks – check your store before placing an order!

Happy New Year everyone!

Yesterday, the German BSI warned (again!) about thousands of online stores worldwide which have been infected by online criminals in order to capture user’s payment data. Many store owner have been informed by the BSI some time ago but less than a half of them have fixed that issue.

Shopping on those still infected or unpatched stores is a high risk! Most likely, your payment data will end up somewhere else.

In 2015, Willem de Groot revealed this issue in the popular shopping software Magento which is widely used around the world.

Which scares me most is the fact that by that time, there were 3501 Stores infected, in March 2016 Willem found 4476 infected stores and late 2016 there were almost 6000 infected stores worldwide. Here is a list:

Fortunately, MageReport provides a tool, to check if a certain website is already infected or at least unpatched and a possible victim for cyber criminals.

So I would recommend to use that tool to check the online shops you are using before using them again.

I did so and guess what, three of them were infected – only one of them replied back to me after I informed them about their issue.


Don’t trust the evil!


NetworkToolbox news

MAC Addresses are back – Happy and secure Holidays

Today, Apple released my Update 9.02.03 which will bring back the MAC Addresses and fixes the Crash in the Device Tool reported by some users.

MAC Addresses

Bringing back the MAC Addresses was really a challenge and caused me some more gray hair and long nights during the last days. With iOS 10.2 Apple continued with their good intentions to protect our privacy by removing all sorts of information that might be misused by developers to uniquely identifying our devices. Apples approach is a good approach and I appreciate that in general. However, this has caused that I was no longer able to show the MAC Addresses in Network Scans anymore which was quite unfortunate as the MAC Addresses were also used along with the included MAC Database to show the vendor of each device. Finding a solution was really a challenge as I have to use official APIs because otherwise Apple would have rejected the App. The solution I found is indeed using official Apple APIs but in a very specific and unusual way (don’t want to elaborate more). This said, I expect Apple to even close this door at some point.

Device Tool crash

This was also a challenge. Some user reported the Device Tool to crash (one user even left a one-star bad review only because of this crash). I tried to reproduce this on any of my various test devices without success. Fortunately, some users contacted me regarding this crash (Thanks again!) and I asked those users to enable crash-log submission in iOS (Settings -> Privacy -> Diagnostics & Usage -> Automatically Send, then enable “Share With App Developers”). When switched on, Crash logs will be submitted to Apple and a few days (sometimes a week) later I am able to download anonymized logs from Apple. These logs showed that indeed for a few users, the App crashed for security reasons as it wasn’t allowed to access motion sensor data (Motion data will be accessed in the Device Tool for the Sensor section). The question is still, why only a few users were affected and why I was (and I am still not) able to reproduce this on all of my test devices. However, I hope at least I fixed this in the new version 9.2.3. If not, please let me know.


Thank you so much for all your reviews. It was overwhelming to read them all. Unfortunately they are now gone with this update but I don’t want to bother you again asking to update your review.

Instead, please have relaxing and secure Holidays.

Thank you all and let’s work together for a more secure 2017!

See you in 2017.

Best regards – and don’t trust the evil.


NetworkToolbox news

iOS 10.2 and missing MAC Addresses

Dear Users,

it seems that Apple has further improved their security measures in iOS 10.2. Unfortunately, this results in wrong MAC Addresses in NetworkToolbox.

I am currently working on a workaround so please be patient and wait for this fix.

Best Regards,


NetworkToolbox news

ALERT: Major attack to Routers. 41 Million Routers worldwide on risk.

alarmMajor attacks to routers are currently ongoing. These attacks already resulted in major outages of the German Telekom network and others in many countries.

The attack is using an old vulnerability on port 7547. This port is basically the interface for the Telecom companies to configure a router remotely. A variant of Mirai currently uses this vulnerability to install a bot using this interface.

Here is, what you can do:

1.) Restart your router

This will clean your router in case it was already affected. However, even after a restart, it may happen that the router will get infected shortly after by another attack as this attack is currently still going on.

2.) Check if your router is vulnerable

For this, you need to perform a reverse (from outside) Portscan on your public IP Address and Port 7547 by following these steps from NetworkToolbox:

– Select the Devices Tool
– Tap on Network
– Locate the Public IP Address
Take down this public IP Address (or bookmark to the Logbook)
Switch off (disable) WiFi mode on your device

Next, ensure that NetworkToolbox can use the Celular/Mobile network as follows:

– Quit NetworkToolbox
– Open Settings
– Tap on Celular Data
– Search for “NET-Toolbox” on the list
– Ensure that the switch for NET-Toolbox is switched ON


– Reopen NetworkToolbox
– Tap on the Portscan Tool
– As Address, enter the Public IP address you took down previously
– As Port enter 7547
– Tap on Scan

You should get an empty list (0 Results). If that’s not the case, your router might be vulnerable.

3.) Protect your router

First of all, you should look for a firmware update. German Telekom currently provides an update for the effected router which is installed automatically after restarting the router. Other may need to look for a router update on the suppliers/vendors website.

After an update has been installed, I would recommend to perform another portscan.

In addition, I suggest to disable this port if possible. Some Routers, like the German Telekom Routers, offer an option to disable the remote configuration feature which will also disable port 7547. On the German Speedport routers this feature is called “Easy Support”. On other routers it might be called “TR-069” or similar.

I would suggest to switch this feature completely off. Please note: if you are using a rented router, your provider may not be happy about this as they can no longer look into your router in case of issues.

Once the port can not be accessed from outside, you should be safe.

Some more background information:

As mentioned before, port 7547 will be used for remote access configurations on your router using a so called TR-069 interface. This interface is quite safe as it uses a callback feature that ensures that only the valid provider can access and change the configuration data.

This interface will also be used for instance by a Synology NAS if you would allow the NAS to configure your router on your behalf for convenience.

However, due to a bug in older implementations of the TR-069 protocol, this interface can also be used for code-injection.

So an open port 7547 alone does not mean you are vulnerable but along with a buggy firmware you are.

Then, either updating the firmware or disabling TR-069 (or closing the port if the router offers such a possibility) would fix a possible issue. If possible, I would suggest to do both (updating and closing the port).



NetworkToolbox news

Mirai and Yahoo


You may have heard about the biggest DDOS attack ever against my colleague Brian Krebs. Brian’s Website has been attacked by devices on the internet which have been compromised by a malware called Mirai (please visit Brian’s website for more details).

I read the source code of Mirai and developed a new security check for you which will be available in NetworkToolbox after checking  for the latest data update in the settings. This new security check will scan for the same vulnerabilities Mirai is using to infect devices.

So you may want to run this security check on some or all of your network devices. If the security check reports a certain device is vulnerable, it doesn’t mean it is already ‘infected’ by Mirai but if Mirai would by chance pass by and visit your network, it is most likely that it will infect that device.

According to what I have seen while inspecting the code, fortunately Mirai will disappear once you restart the infected device. So what you should do, once the new security check reports a vulnerable device is, to restart that device and either remove it from your network or try to update it’s firmware and perform another Security check.


You may also have heard of the latest news about Yahoo.There are three strong arguments why to leave Yahoo as soon as possible:

  1. As mentioned in previous posts, Yahoo is about to be sold. Most likely to Verizon. You may also remember my post of Verizon’s Super-cookie.
  2. 500 Million Yahoo accounts have been hacked.
  3. Yahoo has scanned all mails for NSA and FBI.

A single fact from the above list should be enough to say good bye to Yahoo but I am still surprised to receive many Questions and Support mails from user with Yahoo accounts.

A few weeks ago, I was about to block all Yahoo mails as this would reduce the amount of Spam mails quite a lot (Spam is probably a fourth reason against Yahoo). But since I still receive so many Yahoo mails, I decided against blocking yahoo.

Your question might be, what else should I use? Google? Definitely not! Keep in mind (and this applies very much to Yahoo as well): “Nothing is for free”. Think twice: why should a company who needs to earn money to pay at least their employees offer a service such as Email for free? If you want security, you have to pay – period.

My best advise is, to look for one of the many service Providers who offer simple web-hosting and Email services for a good price and (most important) with a good reputation. Such a provider can be used to register your favorite domain name such as your surname (or combinations like for instance) and they can run a well working Email service for you. This way, you will have personalized and nice Email addresses combined with a reliable and secure Email server. Such (good) providers will also take care of Spam and While/Black listing. Often way better than the big guns like Yahoo or Google.

For a temporary time, you can forward your Yahoo (or Google) mails to this address.

Don’t be trust the evil.


NetworkToolbox news

The Connections tool is gone – which is good!

A very provocative title isn’t it? But yes, it’s true, it is good. I will explain why.

I have received a couple of support mails regarding the no longer working Connections tool. Some people were just wondering when it will come back. Some are blaming Apple for it and one unpleasant person even had nothing else to do than blaming me with loads of unpleasant words and sentences that I don’t want to repeat here (but I will if this person doesn’t stop this).

So what has happened ? I am usually testing compatibility of my Apps with pre-release versions of iOS. In case some action is required I will prepare an update. At some point, Apple released a pre-release that prevented the Connection tool to work. Often, such thing happened and with further pre-releases things get back to normal – and so it does. The Connections tool started working again. But later, with the latest Release Candidate of iOS 10 it discontinued to work again so I started investigating why.

It turned out that Apple has completely removed an API I was using to generate the connection list for the Connections tool. By that date, I investigated in many alternatives which all turned out not to work (anymore or not at all on an i-Device). That was sad as I am also using this Tool quite often, whenever I like to analyze suspicious behavior of newly installed Apps and often discovered bad “calls home” or other undesired connections (e.g. Flurry).

On the other hand, while implementing the Connections tool some time ago, I was even surprised that Apple did offer the API in question as it also allows many other even bad things to do. Other Apps can and likely may have already used the same API for other, undesirable purposes. After implementing the Connections tool and submitting the App to Apple, I also expected that Apple will reject my App – which was obviously not the case.

The problem here is, that even though I call it API, it’s not really a typical “officially documented” API. It was rather a system call with very specific parameters. Such a system call is hard to identify within the review process and that’s probably why. But as mentioned before, this system call can also be used for many other things I definitely don’t want another App to do on my iPhone or iPad.

So even though it’s sad that the Connections Tool can now no longer be used, it is good that this particular API (or System call) is gone. This is indeed a real gain in security and I am hoping Apple will continue to walk this Path. I think it is way more important that our i-Devices can not be compromised and that bad Apps can harm our security and privacy and I think it’s worth the disadvantage that we now no longer have a Connections tool available.

I think Apple is doing a great job by not only continuously adding new great features but also care for security. This is why all my Android Devices (I have quite a few since I used to develop Android Apps as well but discontinued some time ago) remain in my drawer and will not be connected to my internal network. Those devices are quite insecure and exactly the opposite. Google doesn’t care about security and they are even the worst data spy themselves. A Connections tool for Android would still be possible of course but I would not trade any Android Device with any of my iPhones or iPads.

So as you can see, it is very unlikely that the Connections Tool may come back in the future but there is no reason to complain about Apple. They did their job well.

I leave it up to you to decide if it is me who needs to be blamed.

Don’t trust the evil!










NetworkToolbox news

New Update available!


A new version of NetworkToolbox is available.

The new version contains various changes, additions and fixes:

■ Renewed Bluetooth Tool

I have completely re-written the Bluetooth LE scanner. It is now more reliable and easier to use.

■ New Health Check Tool

This new Tool can be used to perform recurring pre-defined tests. You can add multiple sites (IP Addresses or hosts) and perform Ping, Certificate, Mailserver and other tests with a single button press. This way, you can quickly check the availability of components either in your home network or your Internet Servers.

■ New SMB Tool

You can now even browse Windows or other Samba shares using this new Tool. It is also possible to download files.

■ New Speed Test Tool

This new Tool implements the iPerf Speed Test standard and can be used to perform Network Speed/Bandwidth tests to one of the public iPerf Servers or even between two NetworkToolbox Apps running on the Network since the Tool also provides the possibility to run an iPerf Server.

■ Further improved network scan

Now, SMB Network Names and Vendor Names will be displayed in the list itself and not only on the detail screen.

■ Export Settings

As requested, you can now export the settings either for backup purposes or to submit the settings (including the user passwords etc.) to another iOS Device.

■ Reverse DNS and DNS Lookup improved

Even though the Tool is still called NS-Lookup, it is now rather a multipurpose tool that shows all kind of information available to an IP Address or host such as DNS Record information, Revers DNS Lookup, Provider information and more.

■ Macros for Telnet and SSH

It is now possible to write and maintain Macros that can be submitted from inside the Telnet or SSH Tool. Macros also let you sent special Key combinations and supports delays.

■ Other Telnet and SSH improvements

The Keyboard window will now only cover the necessary part of the screen and in case you are using a hardware keyboard, you will now see the full telnet/ssh screen.

Now you can also directly send special keys that are not available on the software or hardware keyboard.

■ WOL (Wake on Lan) has been built in

■ HTTP Head Tool improvements

This Tool now also shows the Status code returned from the Server and an explanation of the meaning this code.

■ IPv6 support

Most Tools now support IPv6 where appropriate. If available, you will see IPv4 as well as IPv6 addresses in the result lists of several tools. You can also enter IPv6 addresses in several Tools in the same way you enter IPv4 addresses.

■ New IP Calculations

With the introduction of IPv6 Addresses, there are also three new Calculations for the IP-Calculation Tool such as IPv4 to IPv6, 6to4/6RD and Teredo calculations.

■ New Manual

As you may already know, this App contains a lot of information and help texts with general information as well as for each individual tool and how to use it (Thanks again to Martin who helped me out here). Several users appreciated that but asked for a separate manual so they can read it side by side with the App. This is now possible. I have moved the existing content and added some more text to a separate manual, which can also be opened from here: but also still from inside the App by hitting the (i) button as usual. If you prefer a printed version, you can also download the manual as PDF file.

■ Bye-bye to the connections Tool

With iOS 10, Apple has removed an API which has been used for the Connections Tool. This means, that this tool no longer works under iOS 10 and you will get an according message if you try to use it. Even though it is not nice that this valuable tool now no longer can be used, Apples decision is a major increase on Security as this API could have also been used for other purposes by any App.

■ Other bug fixes and improvements

Besides the lost Connections Tool, NetworkToolbox is now fully compatible with iOS 10 and even uses some of the new advantages. On an iPad Pro, it can also run in Multitasking and Split Screen mode and it runs just fine on the new iPhone 7 devices.


As you can see, there were many changes with this new Update. It even took quite some time as due to IPv6 Support major parts of the App needed to be re-written.

This said, I wouldn’t be surprised if me or my valued Beta Testers would have missed one or two Bugs. Please don’t worry and just let me know so I can fix it timely.

Updating this App means that it will lose all your nice and kind reviews.

So please, after you installed the update, update your review as well or write a new one.

I hate these annoying nag-screens reminding users to write a review and don’t want to include that.

For your review, you can also tap here.

Thanks for your great support!


Kind regards,


NetworkToolbox news

New Manual and new Version soon

Today, I am happy to announce the new Manual which is now already online for you from here:

Several users found the included (i) Help texts useful but prefer to have the description side by side on another screen or even paper – which makes sense. This, I created the online manual.

Please note: This Manual already covers the next version with many new features and improvements. This new version will have this manual already included also from inside the App but I found it might already be useful for all users of the existing App version.

While talking about the next version. It took quite some time to get it done. This was basically because I had to re-write major parts of the App due to the fact that it now also supports IPv6. There are still some parts of the App which don’t fully work with IPv6 due to some oddities in iOS but I will either fix this during the next days or will leave it as is by now assuming that the majority of you will still use IPv4.

So please stay tuned for my announcement for the release of this update,
Best Regards,

NetworkToolbox news

NetworkToolbox with wired Ethernet connection – not only WiFi anymore! – UPDATE

network-toolbox-and-ethernetSometimes, you may whish to connect to a network via Ethernet Cable in order to inspect or analyze a network. So far with NetworkToolbox it is only possible to connect to a network via Wlan/WiFi.

But there is good news today!

For this reason, some time ago, I bought me the Lightning Ethernet Cable (L2-NET) from Redpark. This cable requires some developments as it’s not supported by any iOS Device itself. I also had to register for Apples MFI Program which is necessary if you want to ship an App which uses a hardware accessory. I did that and I also did already develop almost all necessary changes for NetworkToolbox which was quite a lot as all network routines (especially the scanning and sniffing ones) will have to be adapted for this cable. Unfortunately, at the end, it turned out that the provided Library had some bugs but moreover the Cable often ended up in a situation where I had to completely re-start the device which was the reason why I never released this feature. I was in contact with Redpark a couple of times. They were very kind, committed and helpful but at the end it turned out that the cable issue cannot be solved at least not for NetworkToolbox. If this would change in the future, I will be more than happy to support this cable as I really like it.

However, here is something new:

You can use the new Lightning to USB 3 Camera Adapter along with the USB Ethernet Adapter.

The USB 3 Camera Adapter, which is basically a USB 3 Adapter, was introduced for the new (big!) iPad Pro (the new small iPad Pro doesn’t support USB 3 by the way). I wanted to buy this adapter for my big iPad Pro anyways but added the USB Ethernet Adapter to my order – just in case.

Once the package arrived, I tried to connect both Adapters together and plugged them to my iPad Pro. Then I got a message saying that the Ethernet Adapter consumes too much power and cannot be used.

Two things where surprising with this message: 1.) I didn’t get the usual message saying that this device is not supported, 2.) It even recognizes the second adapter as an “Ethernet Adapter”.

I then put a regular USB hub in between the two Adapters and provided power to the HUB.

Success !!  – as a result, I didn’t see any message anymore but also nothing else. No confirmation message, no additional menus in the Device settings (as it was the case with the L2-NET cable).

Then I switched off WiFi and Cellular, started NetworkToolbox and to my surprised, the Adapter was found and I even got a DHCP Ethernet Address. I was also able to Browser (real fast!) and perform Network scans with NetworkToolbox – pretty cool isn’t it ?

Next, I tried the same with other devices and found that at least my iPad air 2, iPhone 6 and 6s are working well. There may be others working as well but I have not tried it yet.

I then tried to use other HUBs and found that almost all I have are working, except for one old HUB.

I also tried different USB Ethernet Cables which all didn’t work.

I did not try but this solution may even work with the old iPhone Camera Adapter.

So in short, here is what you need:
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If you plug all together and power the USB Hub, switch your iPad/iPhone to Airplane Mode (to disable all other communications), wait a few seconds and then try to use Safari to see if the connection is working. If not, double check the HUB or try another HUB.

Even though NetworkToolbox reports a local IP, it reports a public IP and correct DNS Server and is working very well with this solution.

Please let me know if anybody of you is successfully testing this solution on other devices, or even found that the old Camera Adapter is working well so I can update the compatibility list on this post.

UPDATE: Cristian from Gibraltar just reports that the old USB Camera Adapter works as well with the Ethernet USB Adapter. Thanks Cristian!

Don’t trust the evil!
Best Regards,

NetworkToolbox news

Email tracking even on your iPhone

A dear user and contributor of NetworkToolbox just raised a point I would like to share with you.

While discussing my arguments against Web-Mail services and my suggestion to rather use a Mail client instead, he mentioned that he got frightened some time ago even while using his iPhone mail client. What happened was, that he received an Amazon gift voucher from a relative and while he wanted to thank him five minutes later for the gift, the relative told him that he already knew that he received his gift because he’d just received an email from Amazon informing him about it.

So you may wonder how this could have happened even on a relative secure Apple device. The trick is quite simple and widely used by many newsletters, eCards and even regular mails.There are many service providers offering such a feature to companies even garnished with sophisticated statistics about reading time and even the location of the recipient.

What the do is, they just add a small image (visible or not) to each email. This image has an individual name which is different for every recipient. Once the email has been opened, the email client tries to download this image from the server in order to show the email right.

The Server, where the image comes from just responds with the requested image, maybe an empty 1×1 white pixel. So far so good. But any Web-Server, and the server for such an email image is also a Web-Server, will see the requesting IP Address and, of course, the file name of the requested image. Remember, as mentioned before, the file name is basically a unique Identifier which identifies each recipient and the IP Address will help to track down the location and other information such as type of device (e.g. iPhone) as well as the client software the recipient is using. And of course, all of that is being logged and can trigger an email to somebody who is interested in knowing when you read their mail.

But for iOS users, it’s not too bad at all. There is something one can do against it what the dear user found out on his own while googling. There is a setting under Email settings called “load remote images” (or “Bilder vom Websever laden” for the German users) which should be switched off.

It is very unfortunate that this setting is turned on by default but I would strongly recommend turning it off. This setting will prevent the things I mentioned before from happening. The only disadvantage is, that some mails might look a bit strange without images which will no longer be loaded in the future once this setting has been disabled but it’s often not too bad and you can manually force the images to be reloaded. But then, keep in mind, the sender may (and most likely will) track this.

You may wonder why you see images in mails even while “load remote images” has been switched off. The reason is, that in that case, images have been embedded in the mail and thus, don’t need to be downloaded and thus, can also not be used for tracking. The disadvantage for this approach is, that such mails get bigger, are causing more network traffic while sent out and while downloaded on your device.

So, don’t trust the evil.
Stay safe!

NetworkToolbox news

The worst thing happened

ns-image2What is the worst thing to happen with regards to network security you can imagine?

How about a network device that should care for your network security which has a back-door that allows access by everyone from everywhere? Yes, that’s scary, right?

Exactly this has happened to Juniper users – and we all are affected.

For your information, Juniper is the second largest company selling Routers, Switches, Firewalls and other network products after Cisco. Their products are widely used from small businesses, large companies, Network providers to governmental networks.

Recently Juniper indicated that they had discovered unauthorized code in their ScreenOS software used in their Netscreen firewalls. It turned out that this code contains two back-doors which allows full device access and VPN traffic monitoring. Further investigations revealed that all of their firewalls running software versions shipped from 2013 until recently can be accessed from everywhere by everyone via SSH using any username and password “<<< %s(un=’%s’) = %u”. An update will fix this issue.

So far, it is unknown how this backdoor slipped into their code.

Currently, Morpheus and Shodan finds more the 30.000 of these devices.

Maybe you personally don’t use Juniper hardware but be assured, your Provider, Bank, online Store, Company you are working for may likely use Juniper hardware.

It was good that Juniper offensively informed about their findings so that security researchers were able to start their own investigations. However, it took two years to find the back-doors. My personal assumption is, that organizations like NSA, GCHQ, Asian or Russian organizations are responsible for this and moreover, I further assume that similar Back-doors are available in other Network Devices such as those from Cisco and other “big Players”.

I even now see the other Back-doors I mentioned in my blog (here and here) from a different perspective. Not unlikely that these back-doors were not results of brain-dead developers but have the same source.

Regardless whether my assumptions are correct, many networks are currently at high risk. Even more because not only NSA, GHCQ etc. are able to access our data, now even inexperienced criminals can.

Due to the impact of this issue, there is not much one can do other than to follow following rules that make sense regardless of this impact:
[su_list icon=”icon: check-square-o”]

  • Think twice if you have to give out personal information such as Name, Address, Email Address and payment information. Better enter it for every single transaction rather than let your online shop conveniently store it
  • Use strong passwords and change your passwords regularly
  • Never use one and the same password for different services
  • Never use one service to log into another service (e.g. don’t use “Login with Facebook” for Netflix)
  • If possible, create some fake accounts and fake identities and use them instead of your real accounts where possible
  • Leave Yahoo. If you still have A Yahoo account, close it. Not unlikely that Yahoo will be sold soon so your information might end up somewhere else
  • Better don’t use a public WiFi network without VPN. Rather use your Cell network (3G/4G/LTE) when security is important
  • Use Firefox instead of Internet Explorer
  • Use Ove’s Self-Destructing Cookies plugin or similar in your browser
  • Setup your mail clients to use encrypted passwords and SSL/TLS
  • Better don’t use Web-Mail clients (except for your fake accounts)
  • Never ever use Android devices
  • Never ever use Windows XP anymore
  • Always install updates (for Software and Hardware)
  • Always change default passwords
  • And of course, consider NetworkToolbox to check for security issues


Of course, there is much more we can do but most of the above is either easy to do or simply mandatory and without alternative.

Regardless, I wish you and your families a Merry Christmas and all the Best and secure 2016!


NetworkToolbox news

Linux cheat sheet added

As requested (and to be honest also for my own sake) I added a linux cheat sheet to NetworkToolbox.

This additional information resource doesn’t cover those simple and basic Linux commands. Instead it contains many less known and easy to forget commands, especially for network administration and information gathering.

If some of you are interested even in the simple commands, please drop me a line and I will be happy to add those as well.

In order to install this cheat sheet, just perform a data update by heading to the settings screen of NetworkToolbox, scroll down and press Check for data update.

After the update, you will see a new Icon in the Resources section of the App which contains the new Linux cheat sheet.

Cheat sheet


NetworkToolbox news

Anonymous against IS

Support Anonymous – and don’t trust the evil

NetworkToolbox news

Security check added for the recent Netgear security flaw

I assume you have heard already from the recent findings of exploitable Netgear routers.

If not, here is a brief summary:

Due to another ignorance or security in-awareness of developers of the Netgear router firmware, it is possible to access several (thousands!) Netgear routers from the internet without entering correct credentials. For details see here.

If this alone isn’t scary enough, Netgear has again to be blamed for their slow and ignorant response to this serious security flaw.

Even though Netgear has finally released an update that fixes this issue, still thousand of routers can by found using Morpheus or Shodan which still run the old firmware and thus are exploitable.

To check if your own router is affected, I have written and just release a new security check for NetworkToolbox which can be downloaded by running a data update from the settings screen of NetworkToolbox.

After downloading, you will find a new entry called “Netgear router exploit” in the Security Check tool.

So, better check yourself with NetworkToolbox and don’t trust the evil.



NetworkToolbox news

The truth about XCode Ghost – UPDATE

XCcode Ghost

See my update below.

As this already goes around in the news and not only in the technical press, you will have heard about the XCode Ghost issue and the so claimed “Apple’s biggest malware attack”.

What happened is in short: Some developers, mainly from China downloaded the so called XCode development environment, which is required to develop Apps from dubious websites instead of Apples official website or Apples App Store. The version they downloaded was infected and so were the Apps produced by this XCode version. Some Apps made it to the App Store and some are still available for downloading.

So far, so bad. Scary, isn’t it.

No, it’s not that bad.

Unfortunately, the press and even the people from paloalto networks who “revealed” this story first are currently mystifying this subject rather than informing fully and correctly. They even provide misleading and even obviously wrong information.

So here is my story:

I personally found one of the effected Apps on my device (CamScanner this App has yet been removed from the Store so I can’t provide the link). I reverse engineered this App and can confirm that it indeed contains the XCode Ghost “Virus”.

Further investigation of the code revealed that this code is almost harmless. At least as harmless as all the damn Flurry, AppCrashLog, UserActivity Libraries I am complaining about for quite some time.

It “just” collects even less than Flurry does and submits it to a server ( There is DEFINITELY NO key logger included, NO POPUP will be displayed that asks for an Apple ID/iCloud access or something similar. The rumors about this are absolutely wrong.

Of course, the code could have been more dangerous and my finding depends on just one App so this is not an “all-clear”.

However, most likely it is not as bad as the press writes. There is no prove (maybe yet) that there is any App “infected” in a way that user’s security is affected.

The reason why I am very confident about this is, that I was able to find the source code on the Internet which is 100% identical to the code I found in CamScanner and that also fit’s 100% to the story of paloalto networks. That source code is also garnished with a Chinese “excuse me” of the developer who is claiming to be the author of XCode Ghost.

Take a look yourself here: (maybe use Google translate to read it)

Until there is no further prove otherwise, I assume that this is exactly the code which is included now in some Apps on the App Store.

Apple is currently trying to identify these Apps (which should not be too difficult) and removing them. I however would also expect a list of these Apps from Apple (not like the one on the paloalto website which contains spelling errors and App Names that are available several times on the App Store) so we know which Apps may still reside on our devices.

For your information, and that’s also missing in all the other press statements, you just need to delete the App and it’s gone. There is nothing that remains on your device after you delete it.

And here is, what you can do as NetworkToolbox user:

As explained earlier, my App contains the recently introduced Connections tool. This is ideal to identify such unwanted connections. I just wrote a small tutorial which explains how to detect XCode Ghost using NetworkToolbox.

You may wonder what Apple can do to prevent this from happening in the future. To be honest, so far, there is nothing to blame Apple for right now because (as mentioned before) this code is “harmless” in terms that it doesn’t access secured information and it doesn’t use private APIs. Otherwise I would have been quite sure that Apple would have rejected the Apps (as happened to my Apps).

The most people that have to be blamed are the developers that downloaded XCode from the dubious websites and used it for submitting the Apps to Apple using it. The same thing could definitely have happened on the Microsoft Platform. Maybe even easier because Microsoft does not offer some real App Store approval process at all.Not to talk about Android where there is no protection at all for way easier kind of injections with way more uncontrolled device access.

But I guess, Apple will now most likely speed up and shorten the grace time period for developer of Apps that now have to use HTTPS/TLS rather than HTTP and need to announce and name all domains that their App connects to.


For long time, it seemed that I am the only one claiming that XCode Ghost is relatively harmless. All the so called ‘Security Researchers’, the big press like the German ‘Tagesschau’ and even Heise never got tired of repeating the same story that XCode Ghost has been the biggest hit to iPhone App users security ever and everybody is at risk.

Recently also FireEye (who already is one of my friends) was dared to say that they experienced some MITM (Man in the middle attacks) and offered to “protect their customers” against XCode Ghost.

I sent a lot of mails to those researchers and companies telling them that they are wrong in their assumptions and that they should spend a few minutes in analyzing the code. Probably that was either too difficult for them or they just didn’t listen.

For instance, I asked FireEye what the heck they think how MITM attacks could compromise the users of Apps with XCode Ghost. No answer. Dead end. Probably because the answer is, it makes absolutely no sense at all.

There are still numerous false alarms regarding Phishing and Clipboard interception capabilities of XCode Ghost.

Unfortunately, this all was said by inexperienced, unthinkingly, ignorant, arrogant and attention addictive so called security researchers and the unfortunate so called “press” and security websites just copied and pasted their wrong conclusions.

For me, this is definitely the real issue with XCode Ghost.

Anyway, I gave up repeating the truth about it, hoping many people will read this post and come to their own conclusion.

But it was nice to see that I am finally not alone with my conclusions. See here:

Don’t trust the evil!



NetworkToolbox news

Check for ATM Skimmers with NetworkToolbox

atm2Nowadays, ATM Skimmers use Bluetooth to transfer your stolen credit/debit card details and PIN code.

Brian Krebs today talked about this in a great story where he visited some Hotels in Mexico (even one I stayed in a few years ago) and found several Bluetooth Skimmers.

The hacked ATMs are using Bluetooth modules that are used to download the collected data from the Skimmer inside the ATM. This way, the criminals don’t need to get very close to the ATM to download the stolen data.

Even though this is another scary escalation of the Skimmer technology, the Bluetooth modules can be discovered even by NetworkToolbox. The Modules Brian found are standard Bluetooth modules from a company called Free2Move and that’s also the name these Bluetooth devices are propagating.

There are Bluetooth Modules available for Bluetooth 1.0, 2.0 and even 4.0 (LE) so you will have to discover all three standards. Bluetooth 1.0 and 2.0 devices can simply be discovered by going to the Settings screen of your iPhone, select Bluetooth, switch Bluetooth on if it’s off and wait if your iPhone discovers new Bluetooth devices around you. If you see “Free2Move” when standing close to the ATM you may better want to look for another ATM.

For Bluetooth 4.0 or Bluetooth LE (Low-Energy) you can use the Bluetooth Scanner which is included in NetworkToolbox (Please note: you need to have at least an iPhone 4s for this). Just run a Scan and check the names of the discovered devices and look for “Free2Move” or anything else that doesn’t look obvious.

Of course, the Criminals can change the name but so far, the Skimmers found by Brian Krebs can be discovered this way. At least I will try it whenever I am using an ATM and will let you know once I find a Skimmer or once I got suspected as criminal when standing in front of the ATM and do my scanning ;-).

Don’t trust the evil,

have a secure day,






NetworkToolbox news

WordPress WPML Multilingual plugin – better switch if you still use it

This story is not really related but I had to write it. Simply skip if you don’t use WordPress.

I am using WordPress for most of my Websites and some time ago I purchased the WPML plugin for easier handling of multi-language pages. This plugin wasn’t cheap (about 200 Bucks) but I thought it’s worth it. Little later, after using WPML for a while and after almost getting used to the cumbersome UI and weired bugs, I heard rumors about security issues with WPML. So I looked for updates and headed to their support forum. After reading that they are not really able to fix these issues soon because of issues with their update procedure, I took a look into their PHP code. After this, I knew I have to disable WPML immediate and switch to another solution.

It took me quite some time to find and migrate to another solution but thanks God I did. Later I forgot about WPML.

A few minutes ago, I received the following mail:


So in that mail WPML claims that they updated my password to a strong and secure one (I always thought I am using strong passwords by the way). Further down, they sent me the new password in plain text and EVEN added the Login name (for my convenience I guess) to that mail.

But it got worse. When inspecting the included link they added to the login page (probable even for my convenience) I found it contains the address of a redirect PHP on a completely different server.

At that point, I was pretty sure that this must be one of those usual phishing mails and just in case, I sent a mail to WPML (using the contact form) to inform about this.

Seconds later, they confirmed that this mail was real.

Isn’t that unbelievable ?

I think this finally proves that WPML definitely has no clue about security. So everybody who is still using WPML (probably not too many still) now know that they better switch to something else.

As a site note: WPML can be found on which is ok. But is available for sale. Imagine what happens if a bad guy would acquire But it’s not cheap I must admit.

Anyways, don’t trust the evil.

Best Regards,


NetworkToolbox news

Should we uninstall anti-virus software such as Sophos, ESET, FireEye and Kaspersky ?

Regular readers of my blog know that I am no fan of anti-virus software.

Now, here is another argument against them. Tavis Ormandy recently exploited successfully Kaspersky in a way that users could find their systems easily compromised. Just recently he did the same for Sophos and ESET and even this Sunday, Kristian Erik Hermansen disclosed a zero-day vulnerability in another Malware protection solution from FireEye, which if exploited, results in unauthorized file access.

My personal opinion is that the good old days for those companies are over. Instead of continuing to invest in good security engineers and software developers, they spent their money rather for advertising, fighting against their competitors and seeking for additional ways to make money.

I guess all of you had once your own issues with your preferred virus-scanner or security suite (how they are nowadays called). Dramatical slow-downs, unreachable websites, odd browser behavior, undelivered mails or completely messed up firewall rules. All issues that suddenly disappeared once you switched off or uninstalled the virus scanner. Don’t you ? And for us network admins, isn’t it always scary when the preferred scan engine on the server gets updated because you still remember the server outage due to such an scanner update.

But you thought that this is the price we have to pay for increased security. Now we have learned that we even loose security when using Anti-Virus software.

My suggestion: Don’t use them! Stick with the built-in security measures of Windows, Mac or Linux. Use a good router, use NAT, use Firefox (or if you don’t like Firefox use Chrome for God’s sake) but always keep everything updated. This is all you need for regular browsing and working. The built in Windows defender for instance is not too bad at all. Even though those brave computer magazines regular tests show it never #1 in scanning accuracy. A few pages later you can learn why when reading the big advertisings of these Anti Virus companies.

In addition: if you have to visit suspicious websites or servers or need to access dubious systems or have to do some downloads and to unzip and install files from insecure sources: Never ever do this on your production system. At least setup a virtual machine or better use a separate computer running on a separate IP address space. This is easy to do, easy to recover in case of issues and the best protection you can get.

Don’t trust the evil,

Best regards,










NetworkToolbox news

Babies and families at risk!

Maybe this is another bad coincidence. Shortly after my findings regarding the quite insecure ALDI / MAGINON web cameras, Rapid7 informs about IoT security issues, especially about 10 New Vulnerabilities for Several Video Baby Monitors.


There is nothing to add to this scary report except that this is just again another example of incompetent developers, IT and quality assurance departments of ‘well known’ companies. I hope all of them get fired but maybe they deserve something worse. For instance, that their family or kids get stalked. No – This is something we should not wish to anybody. This would be wrong. But they didn’t seem to care about your family and privacy.

To check your own devices, I just updated the default password database of NetworkToolbox accordingly.

Don’t trust the evil!


P.S. NetworkToolbox now has it’s own dedicated Facebook page.