DEBIAN-CVE-2026-48523
- Source
- https://security-tracker.debian.org/tracker/CVE-2026-48523
- Import Source
- https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-48523.json
- JSON Data
- https://api.osv.dev/v1/vulns/DEBIAN-CVE-2026-48523
- Upstream
- Published
- 2026-05-28T16:16:29Z
- Modified
- 2026-09-17T08:47:30Z
- Severity
-
- 5.4 (Medium) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N CVSS Calculator
- Summary
- [none]
- Details
-
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.decode_complete() are called with a PyJWK key. The token header alg is checked against the caller-supplied algorithms allow-list, but signature verification is performed with the algorithm bound to the PyJWK object instead of the header algorithm. An attacker who controls a registered JWK/JWKS private key can sign with a disallowed algorithm, advertise an allowed algorithm in the JWT header, and still be accepted. The issue affects the documented PyJWKClient.get_signing_key_from_jwt(...) flow. This vulnerability is fixed in 2.13.0.
- References
Affected packages
Debian:13 / pyjwt
Package
- Name
- pyjwt
- Purl
- pkg:deb/debian/pyjwt?arch=source&distro=trixie
Debian:14 / pyjwt
Package
- Name
- pyjwt
- Purl
- pkg:deb/debian/pyjwt?arch=source&distro=forky