Malicious Cactus Ransomware Ransom Note Creation (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 Cactus ransomware ransom notes, which embed the fixed C.A.c_T.U-S-R.e-a_D.m-e marker between randomized prefixes and postfixes in the note filename. Adversaries leverage mass note deployment during the encryption stage, making detection of this distinctive embedded string a reliable late-stage indicator of a Cactus impact event.

Reporting behind it

Related detections9 linkedT1486 — drag to rearrange

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Malicious DEVMAN Ransomware Encrypted File and Note Artifacts

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Malicious Cactus Ransomware Ransom Note Creation (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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