## Authlib incomplete algorithm-confusion fix permits HMAC forgery with prefixed public keys

- 種別: advisory
- 重大度: high
- 関連技術: python
- CVE: CVE-2026-114615
- 公開日時: 2026-10-27T15:38:48.000Z
- 情報源: GitHub Advisory Database (https://github.com/advisories/GHSA-7vr2-2fgp-9w7p)
- パーマリンク: https://vulnpulse.app/items/ghsa-ghsa-7vr2-2fgp-9w7p

影響: pip:authlib >= 1.3.1, <= 1.8.0 → 1.9.0
OctKey.import_key() carries the only guard that stops an asymmetric public key from being used as an HMAC secret in authlib.jose. That guard is raw_key.startswith(POSSIBLE_UNSAFE_KEYS) — anchored at byte 0 — while the loader that consumes the identical bytes on the asymmetric path (cryptography.hazmat.primitives.serialization.load_pem_public_key / load_pem_x509_certificate) skips anything before the -----BEGIN line. A PEM public key or X.509 certificate carrying one leading byte — a newline, a…