CVE-2026-1529 Red Hat CVE debrief

Who should care

Organizations using Keycloak for authentication and authorization should be aware of this vulnerability and take immediate action to mitigate it. This vulnerability could allow attackers to gain unauthorized access to sensitive systems and data. Keycloak administrators should review their systems for potential exposure and apply patches or workarounds as needed.

Technical summary

The vulnerability exists in Keycloak's invitation token system, where an attacker can modify the organization ID and target email in a legitimate invitation token's JWT payload. This allows the attacker to self-register into an unauthorized organization, gaining unauthorized access. The vulnerability is caused by a lack of cryptographic signature verification on the JWT payload. The CVSS vector for this vulnerability is CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N.

Defensive priority

High priority should be given to patching or mitigating this vulnerability, as it could allow attackers to gain unauthorized access to sensitive systems and data. Keycloak administrators should review their systems for potential exposure and apply patches or workarounds as needed.

Recommended defensive actions

• Apply patches or updates provided by the vendor to fix the vulnerability.
• Review Keycloak systems for potential exposure and apply workarounds if patches are not available.
• Monitor systems for suspicious activity related to invitation tokens and self-registration.
• Implement additional security controls, such as multi-factor authentication, to reduce the risk of unauthorized access.
• Conduct a thorough review of Keycloak configurations and settings to ensure they are secure and up-to-date.

Evidence notes

The CVE-2026-1529 vulnerability was published on February 9, 2026, and last modified on June 30, 2026. The vulnerability has a CVSS score of 8.1 and is considered high severity. The CVE record and NVD detail pages provide additional information about the vulnerability, including its CVSS vector and potential impacts.

Official resources