Jonas Wagner

Jonas Wagner is the founder and CTO of Threatray and has built the technological foundation of its code search engine based on years of research and development. He holds a Masters Degree in Cybersecurity from the Bern University of Applied Sciences. He has previously spoken at botconf, FIRST CTI, BSides Zürich, DFRWS and many private events.


Using systematic code reuse analysis to create robust YARA rules
Jonas Wagner, Carlos Rubio Ricote

YARA is a commonly used tool to detect and identify malware. There are roughly two types of YARA rules used on binary files: 1) based on metadata and strings and 2) based on code.
There are certain benefits by basing YARA rules on code. Since code reuse is frequent amongst binaries of a malware family, it offers plenty of options to base a YARA rule on. If the chosen code is heavily reused amongst the binaries, then it can result in very robust rules.
This approach comes with certain challenges. A key aspect is being able to find heavily reused code amongst many binaries of a malware family. Unless some sort of automation is at play, this quickly becomes difficult and time-consuming. Once suitable reused code is identified, it needs to be turned into a YARA rule, so that it works even when compiler differences, optimizations or instruction set changes are involved.
In this workshop we will create robust YARA rules for a handful of malware families based on automatically identifying shared code between many binaries of a family.