NIXPKGS-2026-1799

GitHub issue published on

Permalink CVE-2026-48526

7.4 HIGH

CVSS version (CVSS): 3.1
Attack Vector (AV): Network (N)
Attack Complexity (AC): High (H)
Privileges Required (PR): None (N)
User Interaction (UI): None (N)
Scope (S): Unchanged (U)
Confidentiality (C): High (H)
Integrity (I): High (H)
Availability (A): None (N)
Modified Attack Vector (MAV): Network (N)
Modified Attack Complexity (MAC): High (H)
Modified Privileges Required (MPR): None (N)
Modified User Interaction (MUI): None (N)
Modified Confidentiality (MC): High (H)
Modified Scope (MS): Unchanged (U)
Modified Integrity (MI): High (H)
Modified Availability (MA): None (N)

updated 11 hours ago by @LeSuisse Activity log

Created suggestion 2 days, 21 hours ago
@LeSuisse accepted 2 days, 15 hours ago
@LeSuisse published on GitHub 11 hours ago

PyJWT: Public-key JWK accepted as HMAC secret enables forged HS256 tokens when mixed families are allowed

PyJWT is a JSON Web Token implementation in Python. Prior to 2.13.0, when the verifier is decoding JSON Web Tokens, while supporting both asymmetric and HMAC algorithms, the library does not validate use of JSON Web Keys in HMAC algorithm, allowing attacker to use the issuer public key as the secret key for HMAC algorithm. This vulnerability is fixed in 2.13.0.