CVE-2026-5430
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
The JWT authentication mechanism accepts tokens signed with algorithms other than those explicitly configured or supported. This allows an attacker to craft a JWT with an unsupported algorithm, which is then incorrectly validated, leading to unauthorized access. Successful exploitation of this vulnerability may result in unauthorized access to the system, including the potential compromise of administrative accounts and full account takeover. The CVSS score is adjusted to 9.8 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H) in single-tenant deployments, reflecting that the impact is contained within a single security authority boundary.
Added: 2026-09-24 · Due: 2026-09-27
Known ransomware use: Unknown
As of 2026-10-27
EPSS estimates exploitation probability over the next 30 days. KEV due dates apply to US federal civilian agencies. Confirm your affected versions in vendor advisories.
CWE: CWE-347 · Published: 2026-08-06T08:16:33.240 · Modified: 2026-09-25T12:53:05.517
Sources: NIST NVD, CISA KEV, FIRST EPSS. NVD and EPSS cached up to 6 hours; KEV up to 12 hours.