Possible PowerShell Empire Default User-Agent In HTTP Traffic

PremiumReviewedSigma · Low · v1
Category
proxy
Author
HuntRule
Published
2026-05-02
Updated
2026-08-28

ATT&CK techniques

C2
  1. Recon

  2. Resource Dev

  3. Initial Access

  4. Execution

  5. Persistence

  6. Priv Esc

  7. Defense Evasion

  8. Cred Access

  9. Discovery

  10. Lateral Movement

  11. Collection

  12. Exfiltration

  13. Impact

What it detects

This rule detects outbound HTTP traffic carrying the default user-agent string shipped with the PowerShell Empire C2 framework. In the WithSecure C2 and Exfiltration Lab 1 the Empire agent beacons out with an unmodified Mozilla compatible MSIE user-agent that is characteristic of the framework default profile. Attackers rely on this static header for their staging and command channel unless an operator customizes it.

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Possible PowerShell Empire Default User-Agent In HTTP Traffic
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Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.