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

Possible Akira Ransomware Note or Encrypted Extension Creation

Malicious Storm-2603 Ransom Note File Creation

BitLocker Feature Activation on Multiple Hosts - Native (via bitlocker)

FunkSec Ransomware Encryption Artifacts via funksec Extension and Markdown Ransom Note (via file_event)

INC Ransomware Ransom Note INC-README Written to Disk (via file_event)

Malicious DEVMAN Ransomware Encrypted File and Note Artifacts

Malicious Akira Ransomware Encrypted File Extension via File Event

Malicious BitLocker Abuse for Ransomware via PowerShell (via ps_script)

Malicious WeaXor Ransomware Encryption Artifacts on Disk (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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