CVE-2026-48523 PyJWT: Algorithm allow-list bypass when decoding with `PyJWK` / `PyJWKClient` keys

PyJWT is a JSON Web Token implementation in Python. From 2.9.0 to 2.12.1, there is a verifier-side algorithm allow-list bypass when jwt.decode or jwt.decodecomplete are called with a PyJWK key. The token header alg is checked against the caller-supplied algorithms allow-list, but signature...