What is CVE-2026-44351?

CVE-2026-44351 is a critical-severity vulnerability in Nearform Fast-jwt, classified under Improper Authentication. CVSS score: 9.1/10. Published 2026-05-13.

How severe is CVE-2026-44351?

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

Auth bypass in Nearform Fast-jwt

CVE-2026-44351

fast-jwt provides fast JSON Web Token (JWT) implementation. Prior to 6.2.4, a critical authentication-bypass vulnerability in fast-jwt's async key-resolver flow allows any unauthenticated attacker to forge arbitrary JWTs that are accepted…

Vulnerability class: Broken Authentication

EPSS: 0.000 (3.5th 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 < 6.2.4

Weakness classification (CWE)

CWE-287 — Improper Authentication
CWE-326 — Inadequate Encryption Strength
CWE-1391

References

security-advisories@github.com (x_refsource_CONFIRM)

Frequently asked questions

What is CVE-2026-44351?: CVE-2026-44351 is a critical-severity vulnerability in Nearform Fast-jwt, classified under Improper Authentication. CVSS score: 9.1/10. Published 2026-05-13.
How severe is CVE-2026-44351?: Critical severity. CVSS v3 base score is 9.1 out of 10.