A flaw was found in the jwcrypto library, which is used for implementing Javascript Object Signing and Encryption (JOSE) standards. The issue occurs when the library verifies a General JSON Serialization JWS using a set of keys. Due to a coding error, the library fails to correctly identify the specific key ID (kid) and may instead accept a signature made by any valid key in the set. This can allow an attacker with a valid key to bypass authorization checks in applications that rely on the key ID to identify specific tenants or users.

python313-jwcrypto-1.6.0-1.1 on GA media

Security update for python-jwcrypto

Affected: Ubuntu:16.04:LTS: python-jwcrypto, Ubuntu:18.04:LTS: python-jwcrypto, Ubuntu:20.04:LTS: python-jwcrypto, Ubuntu:22.04:LTS: python-jwcrypto, Ubuntu:24.04:LTS: python-jwcrypto, Ubuntu:26.04:LTS: python-jwcrypto

A flaw was found in the jwcrypto library, which is used for implementing Javascript Object Signing and Encryption (JOSE) standards. The issue occurs when the library verifies a General JSON Serialization JWS using a set of keys. Due to a coding error, the library fails to correctly identify the specific key ID (kid) and may instead accept a signature made by any valid key in the set. This can allow an attacker with a valid key to bypass authorization checks in applications that rely on the key ID to identify specific tenants or users.