Malicious Katz Stealer Command-and-Control via katz-ontop User-Agent (via proxy)

ATT&CK techniques

C2

Recon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
- T1071.001Web Protocols
Exfiltration
Impact

What it detects

This rule detects outbound HTTP requests carrying the distinctive katz-ontop token appended to the User-Agent string by the Katz Stealer implant during command-and-control communication. Adversaries leverage this hardcoded agent identifier to beacon to their infrastructure, making detection valuable for exposing active stealer command-and-control on the network.

Reporting behind it

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Malicious Katz Stealer Command-and-Control via katz-ontop User-Agent (via proxy)

Pivot detection · T1071.001 · 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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