Steal or Forge Authentication Certificates
Where this stands
One published detection covers this technique. Every one is unverified — no rule on Siemphony has been executed against real telemetry.
What the technique is
Adversaries may steal or forge certificates used for authentication to access remote systems or resources. Digital certificates are often used to sign and encrypt messages and/or files. Certificates are also used as authentication material. For example, Entra ID device certificates and Active Directory Certificate Services (AD CS) certificates bind to an identity and can be used as credentials for domain accounts. Authentication certificates can be both stolen and forged. For example, AD CS certificates can be stolen from encrypted storage (in the Registry or files), misplaced certificate files (i.e. Unsecured Credentials), or directly from the Windows certificate store via various crypto APIs. With appropriate enrollment rights, users and/or machines within a domain can also request and/or manually renew certificates from enterprise certificate authorities (CA). This enrollment process defines various settings and permissions associated with the certificate. Of note, the certificate’s extended key usage (EKU) values define signing, encryption, and authentication use cases, while the certificate’s subject alternative name (SAN) values define the certificate owner’s alternate names. Abusing certificates for authentication credentials may enable other behaviors such as Lateral Movement. […]
Read it on attack.mitre.orgWhat MITRE says you would watch
- AN0671
Monitor for abnormal certificate enrollment and usage activity in Active Directory Certificate Services (AD CS), registry access to certificate storage locations, and unusual process executions that attempt to export or access private keys.
- AN0672
Monitor for file access to certificate directories, commands invoking OpenSSL or PKCS#12 utilities to export or modify certificates, and processes accessing sensitive key storage paths.
- AN0673
Monitor for security commands and API calls interacting with the Keychain, as well as file access attempts to stored certificates and private keys in ~/Library/Keychains or /Library/Keychains.
Technique names and descriptions © MITRE ATT&CK®, CC BY 4.0. Not endorsed by MITRE.