Suspicious AiTM Session Cookie Exfiltration to log_cookie Endpoint

ATT&CK techniques

Initial Access → Cred Access

Recon
Resource Dev
Initial Access
- T1078.004Cloud Accounts
Execution
Persistence
- T1078.004Cloud Accounts
Priv Esc
- T1078.004Cloud Accounts
Defense Evasion
- T1078.004Cloud Accounts
Cred Access
- T1539Steal Web Session Cookie
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects web requests to a log_cookie collection endpoint carrying stolen session identifiers such as idx, JSESSIONID, and sid, the harvesting path used by the AiTM phishing kit. The reverse proxy captures live authenticated cookies from M365 and Okta victims and ships them to attacker infrastructure for session hijacking. Traffic to this endpoint with session token parameters indicates successful token theft.

Reporting behind it

Related detections9 linkedT1078.004 — drag to rearrange

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Suspicious Okta SSO Access to Many Applications in Short Window

Suspicious Microsoft Entra Device Code Authentication Flow

Suspicious M365 Password Spraying via Azure PowerShell AppId from Quad7 Botnet

Suspicious AWS Instance Access or Export via SSH Key or Export Task

Suspicious Azure OpenAI Model Enumeration and Deployment Creation (via azure)

Suspicious AiTM Session Cookie Exfiltration to log_cookie Endpoint

Pivot detection · T1078.004 · 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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