CVE-2026-1529 Keycloak affected by improper invitation token validation
Attackers can bypass invitation token signature checks to self-register into unauthorized organizations, gaining illicit access to protected resources.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-1529?
CVE-2026-1529 is a high-severity authentication bypass vulnerability in Red Hat build of Keycloak 26.2, published on 9 Feb 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
A flaw was found in Keycloak. An attacker can exploit this vulnerability by modifying the organization ID and target email within a legitimate invitation token's JSON Web Token (JWT) payload. This lack of cryptographic signature verification allows the attacker to successfully self-register into an unauthorized organization, leading to unauthorized access.
Weakness: CWE-347
Which versions are affected by CVE-2026-1529?
6 open source packages ship an affected version, including org.keycloak:keycloak-services.
| Package | Affected | Fixed in |
|---|---|---|
org.keycloak:keycloak-services Maven | All versions | 26.2.13 |
org.keycloak:keycloak-services Maven | All versions | 26.2.13 |
org.keycloak:keycloak-services Maven | From 26.3.0 | 26.4.9 |
org.keycloak:keycloak-services Maven | From 26.3.0 | 26.4.9 |
org.keycloak:keycloak-services Maven | From 26.5.0 | 26.5.3 |
org.keycloak:keycloak-services Maven | From 26.5.0 | 26.5.3 |
How do I fix CVE-2026-1529?
Upgrade org.keycloak:keycloak-services to a fixed version for your release line: 26.2.13, 26.4.9 or 26.5.3.
Upgrade, and rotate credentials and sessions that may have been exposed. More about Authentication bypass.
Is CVE-2026-1529 being exploited?
There is no known exploitation of CVE-2026-1529 in the wild and no public exploit code.
Public exploit code: 3 proofs of concept on GitHub.
Sources
Also known as ECHO-f035-45d7-d0f3, GHSA-hcvw-475w-8g7p, MINI-j66q-fw3q-j6pj, MINI-vpc7-5ghv-fvwx.