Malicious CRYPTBASE.dll Side-Loading Outside System32

ATT&CK techniques

Execution → Defense Evasion

Recon
Resource Dev
Initial Access
Execution
- T1574.001DLL
Persistence
- T1574.001DLL
Priv Esc
- T1574.001DLL
Defense Evasion
- T1574.001DLL
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
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.

Reporting behind it

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Malicious CRYPTBASE.dll Side-Loading Outside System32

Pivot detection · T1574.001 · 9 related

Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.

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