CVE-2026-44699
Description
A flaw was found in libjwt. This vulnerability allows a remote attacker to bypass authentication by forging a valid JSON Web Token (JWT). The flaw occurs because libjwt accepts an RSA JSON Web Key (JWK) that does not contain an 'alg' parameter as the verification key for HMAC-based tokens. This leads to HMAC (Keyed-Hash Message Authentication Code) verification with a zero-length key, enabling an attacker to create valid tokens without needing the secret or RSA private key.
Statement
Red Hat Product Security has determined that this vulnerability does not affect any currently supported Red Hat product. This assessment may evolve based on further analysis and discovery. For more information about this vulnerability and the products it affects, please see the linked references.
Understanding the Weakness (CWE)
Availability,Integrity,Confidentiality
Technical Impact: Read Memory; Modify Memory; Execute Unauthorized Code or Commands; DoS: Crash, Exit, or Restart
When a memory buffer is accessed using the wrong type, it could read or write memory out of the bounds of the buffer, if the allocated buffer is smaller than the type that the code is attempting to access, leading to a crash and possibly code execution.
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