Suspicious CLFS Base Log File Created in SkyPDF ProgramData Path during Zero-Day Exploitation (via file_event)

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 creation of the CLFS base log file PDUDrv.blf under a SkyPDF ProgramData directory, the on-disk artifact of the Common Log File System zero-day exploitation that precedes privilege escalation and ransomware deployment. Adversaries craft a malicious .blf to trigger the CLFS vulnerability, so this specific file path appearing on a host is a strong indicator of exploitation.

Reporting behind it

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Suspicious CLFS Base Log File Created in SkyPDF ProgramData Path during Zero-Day Exploitation (via file_event)

Pivot detection · T1068 · 9 related

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