Malicious Chaos Ransomware Ransom Note and Encrypted Extension (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 Chaos C++ ransomware writing the ransom note READ_IT.txt into the AppData folder and appending the .chaos extension to encrypted files. Creation of these artifacts indicates active encryption by the locker. The malware also drops debug logs under the temp folder.

Reporting behind it

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Malicious Chaos Ransomware Ransom Note and Encrypted Extension (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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