Suspicious M365 Device Code Authentication Flow via m365

ATT&CK techniques

Initial Access → Cred Access

Recon
Resource Dev
Initial Access
- T1566.002Spearphishing Link
Execution
Persistence
Priv Esc
Defense Evasion
Cred Access
- T1528Steal Application Access Token
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects Microsoft 365 sign-ins that use the device code authentication flow. The Railway PaaS campaign relied on device code phishing to trick users into authorizing attacker-controlled sessions, so device code grants outside of known kiosk or IoT enrollment scenarios indicate probable phishing-driven token theft.

Reporting behind it

Related detections9 linkedT1528 — drag to rearrange

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Suspicious M365 Device Code Authentication Flow via m365

Pivot detection · T1528 · 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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