Auth bypass in Jwt Ruby-jwt

CVE-2026-45363

ruby-jwt is a Ruby implementation of the RFC 7519 OAuth JSON Web Token standard. Prior to 2.10.3 and 3.2.0, JWT.decode(token, '', true, algorithm: 'HS256') accepts an attacker-forged token because OpenSSL::HMAC.digest('SHA256', '', payload…

Vulnerability class: Broken Authentication

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

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-45363?
CVE-2026-45363 is a critical-severity vulnerability in Jwt Ruby-jwt, classified under Improper Authentication. CVSS score: 9.1/10. Published 2026-07-14.
How severe is CVE-2026-45363?
Critical severity. CVSS v3 base score is 9.1 out of 10.