Please refer to the previous blog to have a better understanding of YARA
the focus is on leveraging tools like Cuckoo Sandbox and the Python PE Module to generate YARA rules for malware detection.
Cuckoo Sandbox, an automated malware analysis environment, creates YARA rules based on behaviors observed during malware execution, such as runtime strings.- The Python PE Module analyzes the Windows Portable Executable (PE) structure and generates YARA rules from various sections of PE files, aiding in malware identification without reverse engineering.
other tools like LOKI, THOR, FENRIR, and YAYA.
LOKIis a free open-source IOC scanner utilizing multiple detection methods, including YARA rule checks.THORis a multi-platform IOC and YARA scanner with a free version, THOR Lite.FENRIRis a bash script tool for systems supporting bash,YAYAhelps manage YARA rule repositories.
LOKI,is used by security analysts to research threats and create detection rules based on IOCs and YARA rules. Analysts can run python loki.py -h to see options, use -update to add signature-based directories, inspect YARA files in the yara directory, and scan suspicious files with a specified path.
When LOKI fails to detect threats like a web shell, analysts create YARA rules using yarGen, which automates rule creation by excluding goodware strings. The command python3 yarGen.py -m /path/to/file --excludegood -o /path/to/output generates rules, which analysts should review for false positives.
Valhalla, an online YARA feed, enhances detection capabilities with high-quality YARA rules. It allows searches based on various parameters and provides detailed rule information, facilitating comprehensive threat analysis and response.
Summary:
- using tools like Cuckoo Sandbox and LOKI for generating and managing YARA rules to detect malware.
- creating YARA rules with yarGen when LOKI misses threats.
- Valhalla, an online feed providing high-quality YARA rules for enhanced detection.