Malicious CACTUS Ransomware Note and Encrypted File Artifacts (via file_event)

ATT&CK techniques

Impact

Recon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact
- T1486Data Encrypted for Impact

What it detects

This rule detects creation of the CACTUS ransom note cAcTuS.readme.txt or files renamed with the .cts extension appended during encryption. These artifacts confirm active CACTUS ransomware impact on the host and mark the encryption phase of the intrusion.

Reporting behind it

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Malicious CACTUS Ransomware Note and Encrypted File Artifacts (via file_event)

Pivot detection · T1486 · 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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