Suspicious Reactivation of Guest Account via net user (UAT-8099)

ATT&CK techniques

Persistence

Recon
Resource Dev
Initial Access
Execution
Persistence
- T1136.001Local Account
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects reactivation of the built-in Guest account using net user guest with the active flag. UAT-8099 re-enables and elevates the Guest account to maintain covert administrative access to compromised IIS servers. Enabling the normally disabled Guest account is an account-manipulation persistence technique.

Reporting behind it

Related detections9 linkedT1136.001 — drag to rearrange

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Suspicious Reactivation of Guest Account via net user (UAT-8099)

Pivot detection · T1136.001 · 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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