Malicious RansomHub Ransom Note Creation via README Random Suffix Pattern (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 RansomHub ransom note files following the README_ prefix with a random six-character suffix documented by Group-IB. Adversaries drop these notes across encrypted directories to signal impact and deliver extortion demands, so their appearance indicates active ransomware encryption.

Reporting behind it

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Malicious RansomHub Ransom Note Creation via README Random Suffix Pattern (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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