Malicious Vulnerable Driver Load via TfSysMon.sys BYOVD (via driver_load)

ATT&CK techniques

Priv Esc

Recon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
- T1068Exploitation for Privilege Escalation
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects loading of the TfSysMon.sys vulnerable driver abused by the RansomHub Killer tool to disable security products through bring-your-own-vulnerable-driver as reported by Group-IB. Adversaries load this signed but vulnerable driver to terminate AV and EDR processes from kernel space, making its load a strong defense-evasion indicator.

Reporting behind it

Related detections9 linkedT1685 — drag to rearrange

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Malicious Removal of Defender Safe Mode Service Registration via Process Creation

Suspicious Windows Defender Weakening via MpPreference (via process_creation)

Malicious Whole-Drive Defender Exclusion via Add-MpPreference (via ps_script)

Malicious Vulnerable Driver Load via TfSysMon.sys BYOVD (via driver_load)

Pivot detection · T1685 · 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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