Detections
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CVE-2026-5430

critical

Description

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.

References

https://security.docs.wso2.com/en/latest/security-announcements/security-advisories/2026/WSO2-2026-5328/

https://www.securityweek.com/enterprises-warned-of-attacks-exploiting-wso2-vulnerability/

https://thehackernews.com/2026/09/active-exploitation-attempts-target.html

Details

Source: Mitre, NVD

Published: 2026-08-06

Updated: 2026-08-10

Risk Information

CVSS v2

Base Score: 10

Vector: CVSS2#AV:N/AC:L/Au:N/C:C/I:C/A:C

Severity: Critical

CVSS v3

Base Score: 10

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H

Severity: Critical

EPSS

EPSS: 0.00223

Vulnerability Watch

Tenable Research has classified this CVE under the following Vulnerability Watch classification, which includes active and historical (inactive) classifications. You can learn more about these classifications on our blog.

Vulnerability of Interest