No VulnCrest analysis published for this CVE yet. Below is the original CNA/NVD description, unmodified.
Description
python-jose through 3.5.0 contains an authentication bypass vulnerability that allows unauthenticated attackers to forge JWTs because HMACKey and CryptographyHMACKey accept zero-length HMAC secrets. When an application's HS256/HS384/HS512 verification key resolves to empty, such as an oct JWK with empty k, attackers can forge tokens with arbitrary claims that jwt.decode accepts.
Exploits & detection
No public PoC or detection template found yet.
Timeline
- Published: 02 Nov 2026
- Last modified upstream: 09 Nov 2026
Sources & licenses
- CVE / CVSS / CWE
- NVD record ↗ (unmodified). This product uses the NVD API but is not endorsed or certified by the NVD. CVE® © The MITRE Corporation.
- Exploitation
- CISA KEV (CC0) · EPSS by FIRST.org
- References used for the analysis
- https://github.com/mpdavis/python-jose/blob/3.5.0/jose/backends/cryptography_backend.py
- https://github.com/mpdavis/python-jose/blob/3.5.0/jose/backends/native.py
- https://github.com/mpdavis/python-jose/issues/398
- https://www.vulncheck.com/advisories/python-jose-through-3.5.0-authentication-bypass-via-empty-hmac-key
- Analysis, summary and remediation
- © VulnCrest