Description

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.

INFO

Published Date :

2026-04-06T15:54:03.765Z

Last Modified :

2026-04-06T18:43:16.088Z

Source :

GitHub_M
AFFECTED PRODUCTS

The following products are affected by CVE-2026-34950 vulnerability.

Vendors Products
Nearform
  • Fast-jwt
REFERENCES

Here, you will find a curated list of external links that provide in-depth information to CVE-2026-34950.

URL Resource
https://github.com/nearform/fast-jwt/security/advisories/GHSA-mvf2-f6gm-w987 cve-icon cve-icon
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