Suspicious Whisper Backdoor Log File in Windows Temp

ATT&CK techniques

C2

Recon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
- T1071.001Web Protocols
Exfiltration
Impact

What it detects

This rule detects creation of a file named WindowsEventLogs.txt in C:\Windows\Temp, the hardcoded log location written by the Whisper backdoor used by the BladedFeline group. The filename masquerades as legitimate event log data while actually storing attacker command output and activity records.

Reporting behind it

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Suspicious Whisper Backdoor Log File in Windows Temp

Pivot detection · T1071.001 · 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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