Suspicious browsercore Execution from Anomalous Parent for PRT Cookie (via process_creation)

ATT&CK techniques

Defense Evasion → Lateral Movement

Recon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
- T1550.001Application Access Token
Cred Access
Discovery
Lateral Movement
- T1550.001Application Access Token
Collection
C2
Exfiltration
Impact

What it detects

This rule detects browsercore.exe launched by a process other than a known browser or task host, a pattern used to request a PRT cookie for cloud authentication abuse. The cloud lateral-movement research shows attackers invoke browsercore outside its normal browser context to obtain single sign-on artifacts. An unexpected parent for this binary is a heuristic sign of token theft.

Reporting behind it

Related detections9 linkedT1550.001 — drag to rearrange

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Suspicious browsercore Execution from Anomalous Parent for PRT Cookie (via process_creation)

Pivot detection · T1550.001 · 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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