Possible Ransomware Note or Encrypted File Extension Creation

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 ransom note files or files renamed with encrypted extensions used by the ransomware families compared in this research. The specific note names and extensions appear only after data has been encrypted on the victim host. Detecting them confirms an active encryption event so responders can isolate the machine.

Reporting behind it

Related detections9 linkedT1486 — drag to rearrange

Malicious Ransomware Encryption Extension x2anylock

Malicious Fivehands Go Encryptor Execution via Command Line Flags

Malicious SafePay Ransomware Encryptor Command-Line Execution

Malicious The Gentlemen Ransomware Encryptor via Distinctive CLI Flags

Malicious GigaWiper Ransomware File Extension .candy

Malicious Forced BitLocker Encryption for Extortion (via process_creation)

Malicious Volume Shadow Copy Deletion via Vssadmin

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

Malicious Macaw Ransom Note or Encrypted File Written (via file_event)

Possible Ransomware Note or Encrypted File Extension Creation

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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