Weak Authenticode timestamp counter-signature digest algorithm

ID PE178 Level ERROR Category Security

Description

Authenticode timestamp counter-signature digest algorithm is too weak. This may allow an attacker to modify the executable while keeping the signature valid.

Mitigation

  • Use stronger hash algorithm when signing the image. MD5 and SHA1 algorithms are no longer considered safe. Use SHA256, SHA384 or SHA512.
  • When signing the image using signtool, pass the /td option with the strong hash name (e.g. /td SHA256). See the signtool description page for more details.

Arguments

This rule has the following output arguments:

  • signature_info - Readable affected signature name (e.g. "root signature", "timestamp root signature", "nested signature (index 1)")
  • hash_algorithm - Weak hash algorithm used in the signature (e.g. MD5, SHA1)