CAPEC-476 - Signature Spoofing by Misrepresentation

An attacker exploits a weakness in the parsing or display code of the recipient software to generate a data blob containing a supposedly valid signature, but the signer's identity is falsely represented, which can lead to the attacker manipulating the recipient software or its victim user to perform compromising actions.

Severity

Likelihood

Confidentiality

Integrity

Availability

  • Attack Methods 2
  • Protocol Manipulation
  • Spoofing

High level: Attacker needs to understand the layout and composition of data blobs used by the target application.

High level: To discover a specific vulnerability, attacker needs to reverse engineer signature parsing, signature verification and signer representation code.

High level: Attacker may be required to create malformed data blobs and know how to insert them in a location that the recipient will visit.

Recipient is using signature verification software that does not clearly indicate potential homographs in the signer identity.

Recipient is using signature verification software that contains a parsing vulnerability, or allows control characters in the signer identity field, such that a signature is mistakenly displayed as valid and from a known or authoritative signer.

Ensure the application is using parsing and data display techniques that will accurately display control characters, international symbols and markings, and ultimately recognize potential homograph attacks.