Malicious Root Certificate Installed via certutil addstore for AiTM Interception

ATT&CK techniques

Defense Evasion → Collection

Recon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
- T1553.004Install Root Certificate
Cred Access
- T1557Adversary-in-the-Middle
Discovery
Lateral Movement
Collection
- T1557Adversary-in-the-Middle
C2
Exfiltration
Impact

What it detects

This rule detects certutil.exe adding a certificate to the root or CA store using the addstore and Enterprise options. Microsoft observed Secret Blizzard installing a rogue root certificate to enable adversary-in-the-middle interception of diplomat traffic. Trusting an attacker root certificate allows silent TLS decryption, so this command reveals the interception setup.

Reporting behind it

Related detections9 linkedT1557 — drag to rearrange

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Suspicious Tycoon Phishing-as-a-Service Credential Exfiltration Path (via proxy)

Suspicious OfficeHome Sign-In With Axios User Agent via Tycoon 2FA Proxy

Suspicious AWS AiTM Phishing Kit Endpoint Access via Proxy

Possible AiTM Phishing Sign-On Evaluation Denied by Okta FastPass

Malicious Evilginx AiTM Phishing Proxy Default TLS Certificate

Malicious Root Certificate Installed via certutil addstore for AiTM Interception

Pivot detection · T1557 · 9 related

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