DeepSec 2019 Wrap-Up Day #2

Here we go for the second wrap-up! DeepSec is over, flying back tomorrow to Belgium. My first choice today was to attend: “How To Create a Botnet of GSM-devices” by Aleksandr Kolchanov. Don’t forget that GSM devices are not only “phones”. Aleksandr covered nice devices like alarm systems, electric sockets, smart-home controllers, industrial controllers, trackers and… smartwatches for kids!

They all have features like to send notifications via SMS, call pre-configured numbers but also be configured or polled via SMS. Example of attacks? Brute-force the PIN code, spoof calls, use “hidden” SMS commands. Ok, but what are the reasons to hack them? We have direct attacks (unlock the door, steal stuff) or spying: abuse the built-in microphone. Attacks on the property are also interesting: switch off electric devices (a water pump, a heating system). Also terrorism or political actions? Financial attacks (call or send SMS to premium numbers). Why a botnet? The get some money! Just use it to send huge amounts of SMS but also to DoS or for political/terrorism actions: Can you imagine thousands of alarms at the same time. Thanks to powerful marketing, people buy them so we have many devices in the wild:

  • Default settings
  • Stupid vulnerabilities
  • Not properly installed
  • Insecure by default
  • Cheap!
  • Absence of certification

After the introduction, Aleksandr explained how he performed attacks against different devices. It’s easy to hack them but the real challenge is to find targets. How? You can do a mass scanning and call all numbers but it will cost money and some operators will detect you (“Why are your calling xxx times per day?”) How to search without making a call? They are web services provided by some operators that help to get info about used numbers, they are open API, databases, leaked data, etc… Once you have enough valid devices, it’s time to build the botnet:

Scan > Identify > Attack > Change settings > Profit!

It was an interesting talk to kick off the day!

The next talk was about… pacemakers! Wait, everything has been said about those devices, right? A lot of material has already been published. The big story was in 2017 when a big flaw was discovered. The talk presented by Tobias Zillner was called “500.000 Recalled Pacemakers, 2 Billion $ Stock Value Loss – The Story Behind”.

When you need to assess such medical devices, where to get one? On a second-hand webshop! Just have a look at, their stock of medical devices is awesome! The eco-system tested was: pacemakers / programmers/home monitors and the “Merlin Net” alias “the cloud”. The first attack vector covered by Tobias was the new generation of devices that use wireless technologies (SDR), low power, short-range (2M) – 401-406Mhz). How to find technical specs? Just check the FCC-ID and search for it. Google remains always your best friend. The vulnerabilities found were an energy depletion attack (draining the battery) and a… crash of the pacemaker! The next target was the “Merlin@Home” device which is a home monitoring system. They are easy to find on eBay:

Just perform an attack like against any embedded Linux device: Connect a console, boot it, press a key to get the bootloader, change the boot command add “init=/bin/bash” like any Linux and boot in single-user mode! Once inside the box, it’s easy to find a lot of data left by developers (source code, SSH keys, encryption keys, source code, … The second part of the talk was dedicated to the full-disclosure process.

After a short coffee break, Fabio Nigi presented “IPFS As a Distributed Alternative to Logs Collection”. The idea behind this talk was to try to solve a classic headache for people who are involved in log management tasks. This can quickly become a nightmare due to the ever-changing topologies, the number of assets, amount of logs to collect and process. Storage is a pain to manage.

So, Fabio had the idea to use IPFS. IPFS means “Interplanetary file system” and is a P2P distributed file system that helps to store files in multiple locations. He introduced the tool, how it works (it look interesting, I wasn’t aware of it). Then he demonstrated how to interconnect it with a log collection solution using different tools like IPFS GW, React, Brig or Minerva. It’s an interesting approach, however, the project is still in the development phase (as stated on the website)…

There were many interesting talks today and, with a dual-track conference, it’s not always easy to choose the one that will be the most entertaining or interesting. My next choice was “Extracting a 19-Year-Old Code Execution from WinRAR” by Nadav Grossman.

WinRAR is a well-known tool to handle many archive formats. As the tool is very popular, it’s a great target for attackers because it is installed on many computers! After a very long part about fuzzing (the techniques, tools like WinAFL), Nadav explained how the vulnerability was found. It was located in a DLL used to process ACE files. Many details were disclosed and, if you are interested, there is a blog post available here. Note that since the vulnerability has been found and disclosed, the support of ACE archives has been removed from the last versions of WinRAR!

After the lunch break, I attended “Setting up an Opensource Threat Detection Program” by Lance Buttars (Ingo Money). This was an interesting talk about tools that you can deploy to protect your web services but also counterattack the bad guys. Many tools are used in Lance’s arsenal (ModSecurity, Reverse proxies, Fail2ban, etc…)

Lance also explained what honeypots are and the different types of data that you collect: domains, files, ports, SQL tables or DB. For each type, he gave some examples. Note that “active defense” is not allowed in many countries!

And the day continued with “Once Upon a Time in the West – A story on DNS Attacks” by Valentina Palacín and Ruth Esmeralda Barbacil. They reviewed well-known DNS attack techniques (DNS tunneling, hijacking, and poisoning) then they presented a timeline of major threats that affected DNS services and that abused the protocols like:

  • DNSChangerOperation Ghost Click
  • Syrian Electronic Army
  • Craiglist Hijacked
  • Oilrig: Suspected Iranian
  • Project Sauron (suspected USA)Darkhydrus (
  • Bernhard PoS
  • FIN7
  • DNSpionage
  • SeaTurtle

For each of them, they applied the Mitre ATT&CK framework. Nothing really new but a good recap which concludes that DNS is a key protocol and that it must be carefully controlled.

The two next talks focused more on penetration testing: “What’s Wrong with WebSocket APIs? Unveiling Vulnerabilities in WebSocket APIs
by Mikhail Egorov. He already published a lot of researches around WebSocket and started with a review of the protocol. Then he described different types of attacks. The second one was “Abusing Google Play Billing for Fun and Unlimited Credits!” by Guillaume Lopes. Guillaume explained how Google provides a payment framework for developers. Like the previous talk, it started with a review of the framework then how it was abused. He tested 50 apps, 29 were vulnerable to this attack. All developers were contacted and only 1 replied!

To close the day, Robert Sell presented “Techniques and Tools for Becoming an Intelligence Operator“. Open-source intelligence can be used in many fields: forensics, research, etc. Robert defines it as “Information that is hard to find but freely available”.

He explained how to prepare yourself to perform investigations, which tools to use, network connections, creation of profiles on social network and many more. The list of tools and URLs provided by Robert was amazing! Don’t forget that good OpSec is important. If you’re excited to search for information about your target, (s)he won’t probably be as excited as you! Also, keep in mind, that all techniques used can also be used against you!

That’s all Folks! DeepSec is over! Thanks again to the organizers for a great event!

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