Suspicious CrazyHunter BYOVD Driver Drop in Public Directory

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 the CrazyHunter ransomware dropping its malicious crazyhunter.sys driver or the vulnerable Zemana zam64.sys driver into the C:\Users\Public directory. CrazyHunter uses a Bring Your Own Vulnerable Driver technique to disable endpoint security from kernel space, so writing these driver files to a staging path precedes tampering with defenses and privilege escalation.

Reporting behind it

Related detections9 linkedT1068 — drag to rearrange

Malicious EDR Evasion Driver Load from AnyDesk Directory via k.sys (via image_load)

Malicious Zemana Vulnerable Driver Load for EDR Termination (via image_load)

Suspicious EDRKillShifter Vulnerable Driver Load from User Temp Directory (via image_load)

Suspicious Process Explorer Kernel Driver Dropped as PED.sys via File Creation (via file_event)

Suspicious Dell DBUtilDrv2 Vulnerable Driver Load via driver_load

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

Malicious Vulnerable Driver Load by GentleKiller BYOVD EDR Killer

Malicious Known Vulnerable Driver Load for BYOVD Attack

Malicious Qilin EDR Killer BYOVD Driver Load

Suspicious CrazyHunter BYOVD Driver Drop in Public Directory

Pivot detection · T1068 · 9 related

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