What is CVE-2026-34950?

CVE-2026-34950 is a critical-severity vulnerability in Nearform Fast-jwt, classified under Use of a Broken or Risky Cryptographic Algorithm. CVSS score: 9.1/10. Published 2026-04-06.

How severe is CVE-2026-34950?

Critical severity. CVSS v3 base score is 9.1 out of 10.

Vulnerability in Nearform Fast-jwt

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 the key string, re-enabling the exact s…

Vulnerability class: POODLE (CVE-2014-3566)

EPSS: 0.000 (7.5th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 9.1 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N.

Affected products

Nearform Fast-jwt — versions <= 6.1.0

Weakness classification (CWE)

CWE-327 — Use of a Broken or Risky Cryptographic Algorithm

References

https://github.com/nearform/fast-jwt/security/advisories/GHSA-mvf2-f6gm-w987 (x_refsource_CONFIRM)

Frequently asked questions

What is CVE-2026-34950?: CVE-2026-34950 is a critical-severity vulnerability in Nearform Fast-jwt, classified under Use of a Broken or Risky Cryptographic Algorithm. CVSS score: 9.1/10. Published 2026-04-06.
How severe is CVE-2026-34950?: Critical severity. CVSS v3 base score is 9.1 out of 10.