Malicious CRYPTBASE.dll Side-Loading Outside System32

PremiumReviewedSigma · High · v1
Product
windows
Category
image_load
Author
HuntRule
Published
2026-05-01
Updated
2026-08-28

ATT&CK techniques

Execution → Defense Evasion
  1. Recon

  2. Resource Dev

  3. Initial Access

  4. Execution

  5. Persistence

  6. Priv Esc

  7. Defense Evasion

  8. Cred Access

  9. Discovery

  10. Lateral Movement

  11. Collection

  12. C2

  13. Exfiltration

  14. Impact

What it detects

This rule detects CRYPTBASE.dll being loaded from a directory outside the Windows System32 folder. The CPU-Z and HWMonitor watering-hole campaign side-loaded a malicious CRYPTBASE.dll next to a trusted binary to hijack execution as reported by Kaspersky. Because the genuine CRYPTBASE.dll ships only in System32, loading it from any other path is a reliable DLL search-order hijack indicator.

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Malicious CRYPTBASE.dll Side-Loading Outside System32
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Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.