Description
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.
Affected products
pyjwt_project: pyjwt
References10
- github.com/jpadilla/pyjwt/security/advisories/GHSA-xgmm-8j9v-c9… ExploitVendor Advisory
- access.redhat.com/errata/RHSA-2026:25902
- access.redhat.com/errata/RHSA-2026:25928
- access.redhat.com/errata/RHSA-2026:26206
- access.redhat.com/errata/RHSA-2026:28571
- access.redhat.com/errata/RHSA-2026:30076
- access.redhat.com/errata/RHSA-2026:30088
- access.redhat.com/errata/RHSA-2026:30089
- access.redhat.com/errata/RHSA-2026:33683
- access.redhat.com/errata/RHSA-2026:34160
Metrics
- CVSS 3.1
-
7.4
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N - EPSS — exploit probability
- 0% percentile: 37 · as of 15 November 2026
- CWE
- CWE-287CWE-347
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