Add .NET Environment.TickCount timing anti-debug rule#1137
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aryanyk wants to merge 2 commits intomandiant:masterfrom
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Add .NET Environment.TickCount timing anti-debug rule#1137aryanyk wants to merge 2 commits intomandiant:masterfrom
aryanyk wants to merge 2 commits intomandiant:masterfrom
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mike-hunhoff
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Mar 19, 2026
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@aryanyk there appears to be unrelated rules included in this pull request. Please remove these unrelated rules. Also, please build the referenced anti-debug .NET project and open a pull request to https://github.com/mandiant/capa-testfiles for the resulting binary so we can ground all related rules, thank you.
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Thanks for the feedback @mike-hunhoff I've removed the unrelated rules from this PR. I have also created a minimal .NET sample implementing the timing-based anti-debug technique and opened a PR to capa-testfiles to include this sample: mandiant/capa-testfiles#304 . Please let me know if any further adjustments are needed. |
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This PR adds a rule to detect timing-based anti-debug checks in .NET binaries that rely on repeated reads of
Environment.TickCountaroundThread.Sleep.Issue #596
The technique appears in the
.NET-Anti-Debugproject. A minimal sample implementing the behavior was compiled, features were inspected usingscripts/show-features.py, and the rule was verified to trigger correctly with capa.Example detection:
Additional rules for other techniques in the same project (e.g., WMI-based VM detection and process enumeration) will be submitted in follow-up PRs after validating samples.