CVE-2026-5430: Authentication Bypass via JWT Algorithm Mismatch in Multiple WSO2 Products Allows Account Takeover
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.
Affected Software
Event History
Frequently Asked Questions
What is the severity of CVE-2026-5430?
The severity of CVE-2026-5430 is critical with a score of 10.
How do I fix CVE-2026-5430?
To mitigate CVE-2026-5430, ensure that only supported algorithms are configured for JWT validation in your WSO2 products.
What products are affected by CVE-2026-5430?
CVE-2026-5430 affects WSO2 Identity Server, WSO2 API Manager, and WSO2 Enterprise Integrator.
What type of vulnerability is CVE-2026-5430?
CVE-2026-5430 is an authentication bypass vulnerability caused by a JWT algorithm mismatch.
What can an attacker do with CVE-2026-5430?
An attacker can exploit CVE-2026-5430 to gain unauthorized access and potentially take over user accounts.