Possible EndRAT C2 Communication via Distinctive Client Identifier
- Product
- windows
- Category
- network_connection
- Author
- HuntRule
- Published
- 2026-09-25
- Updated
- 2026-09-25
ATT&CK techniques
C2Recon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
Exfiltration
Impact
What it detects
This rule detects network traffic containing the EndRAT-specific identifiers endServer9688 or endClient9688, string markers observed in Operation Poseidon where the AutoIt-delivered EndRAT implant used these tokens to communicate with its command-and-control server. It captures the beaconing of a specific remote-access trojan by its protocol constants. Detecting this is important because these identifiers are unique to the malware family and provide a high-confidence signal of active compromise.
Reporting behind it
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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Also included
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