CVE catalog

CVE-2026-34950

fast-jwt provides fast JSON Web Token (JWT) implementation. In 6.1.0 and earlier, the publicKeyPemMatcher regex in fast-jwt/src/crypto.js uses a ^ anchor that is defeated by any leading whitespace in

[CVE catalog]

Severity
Critical · CVSS 9.1CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
Published
Source
[NVD] · [CVE record]
EPSS
0.24% · Oct 25, 2026

fast-jwt provides fast JSON Web Token (JWT) implementation. In 6.1.0 and earlier, the publicKeyPemMatcher regex in fast-jwt/src/crypto.js uses a ^ anchor that is defeated by any leading whitespace in the key string, re-enabling the exact same JWT algorithm confusion attack that CVE-2023-48223 patched.

Vulnerable and fixed packages

Distribution-reported package versions and fixes. These do not depend on matching against the OpenFactory package catalog.

DistributionPackageReleaseVersionStatus
Cpefast-jwtNot reported6.2.0fixed
Cpefast-jwtNot reported6.2.0fixed

Fixed-version evidence

DistributionPackageTypeReleaseFixed versionUrgencyOriginBugs
Cpefast-jwtcpeNot reported6.2.0Not reportedNot reportedNot reported
Cpefast-jwtcpeNot reported6.2.0Not reportedNVD-CVE-2026-34950Not reported

OpenFactory catalog packages

No matching packages in this catalog.

Observed:

References