Suspicious C2Looper Shell Output Artifact File Creation (via file_event)

ATT&CK techniques

Collection

Recon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
- T1074.001Local Data Staging
C2
Exfiltration
Impact

What it detects

This rule detects creation of the c2_out.txt file that the first version of C2Looper uses to capture the output of shell commands before exfiltrating it. This hardcoded output filename is characteristic of the backdoor.

Reporting behind it

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Suspicious C2Looper Shell Output Artifact File Creation (via file_event)

Pivot detection · T1074.001 · 7 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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