The Follina 0day vulnerability (CVE-2022-30190) in Microsoft Windows is actively exploited in-the-wild and highly critical. This blog posts lists some important web resources and the signatures that detect exploitation attempts.Kevin's post contains links to tweets of...
Changes in Upcoming THOR Version 10.3
Refactored Handle Detection We have completely refactored THOR's malicious Handle detection. We now allow the use of regular expressions and combined all types in a single signature file named "malicious-handles.dat". Users can provide custom indicators by placing a...
50 Shades of YARA
A long time ago I've noticed that there is no single best YARA rule for a given sample, but different best solutions depending on the user's requirements and use case. I noticed that I often create 2 to 3 YARA rules for a single sample that I process, while each of...
YARA Rule Sets and Rule Feed
As previously announced our YARA rule packs and feeds will be available in March/April 2019. We've put a lot of effort into a internal system named "Mjolnir" that parses, normalizes, filters, tags and automatically modifies our rule base, which contains more than 9000...
Short Tutorial: How to Create a YARA Rule for a Compromised Certificate
Working in incident response or malware analysis, you may have come across compromised and sometimes revoked certificates used to sign malware of different types. Often threat groups use stolen certificates to sign their malware. I'd like to show you an easy way to...
YARA Rule Creation Crackme
I’ve collected some interesting samples for an internal YARA rule creation training session with our interns. With this blog post, I'll also share 3 new premium feed YARA rules by pushing them to the Open Source signature-base repo. What are the the preliminary...
SPARK Core – Free IOC and YARA Scanning
It is done! Our new free scanner SPARK Core has been released. After weeks of planning, development and testing, we're proud to provide the community with a new and powerful multi-platform scanner. SPARK Core is a reduced version of our successful scanner SPARK. The...
How to Write Simple but Sound Yara Rules – Part 2
Months ago I wrote a blog article on "How to write simple but sound Yara rules". Since then the mentioned techniques and tools have improved. I'd like to give you a brief update on certain Yara features that I frequently use and tools that I use to generate and test...
How to Write Simple but Sound Yara Rules
During the last 2 years I wrote approximately 2000 Yara rules based on samples found during our incident response investigations. A lot of security professionals noticed that Yara provides an easy and effective way to write custom rules based on strings or byte...