CAPEC-476: Signature Spoofing by Misrepresentation

Description
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.
Extended Description

Signature verification algorithms are generally used to determine whether a certificate or piece of code (e.g. executable, binary, etc.) possesses a valid signature and can be trusted.

If the leveraged algorithm confirms that a valid signature exists, it establishes a foundation of trust that is further conveyed to the end-user when interacting with a website or application. However, if the signature verification algorithm improperly validates the signature, either by not validating the signature at all or by failing to fully validate the signature, it could result in an adversary generating a spoofed signature and being classified as a legitimate entity. Successfully exploiting such a weakness could further allow the adversary to reroute users to malicious sites, steals files, activates microphones, records keystrokes and passwords, wipes disks, installs malware, and more.

Severity :

High

Possibility :

Low

Type :

Detailed
Relationships with other CAPECs

This table shows the other attack patterns and high level categories that are related to this attack pattern.

Prerequisites

This table shows the other attack patterns and high level categories that are related to this attack pattern.

  • 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.
Skills required

This table shows the other attack patterns and high level categories that are related to this attack pattern.

  • High Attacker needs to understand the layout and composition of data blobs used by the target application.
  • High To discover a specific vulnerability, attacker needs to reverse engineer signature parsing, signature verification and signer representation code.
  • High Attacker may be required to create malformed data blobs and know how to insert them in a location that the recipient will visit.
Taxonomy mappings

Mappings to ATT&CK, OWASP and other frameworks.

Related CWE

A Related Weakness relationship associates a weakness with this attack pattern. Each association implies a weakness that must exist for a given attack to be successful.

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