high8.1
CVE-2026-2603
Keycloak: Unauthorized authentication via disabled SAML Identity Provider
Impact
A flaw was found in Keycloak. A remote attacker could bypass security controls by sending a valid SAML response from an external Identity Provider (IdP) to the Keycloak SAML endpoint for IdP-initiated broker logins. This allows the attacker to complete broker logins even when the SAML Identity Provider is disabled, leading to unauthorized authentication.
Affected packages
| Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|
| maven | org.keycloak:keycloak-services | < 26.5.5 | 26.5.5 |
| maven | org.keycloak:keycloak-server-spi-private | < 26.5.5 | 26.5.5 |
Affected products
| Vendor | Product | Affected versions |
|---|---|---|
| Redhat | Build Of Keycloak | from 26.2 before 26.2.14 from 26.4 before 26.4.10 |
Weakness classification
References
- NVD record
- CVE.org record
- GitHub advisory
- https://access.redhat.com/errata/RHSA-2026:3925
- https://access.redhat.com/errata/RHSA-2026:3926
- https://access.redhat.com/errata/RHSA-2026:3947
- https://access.redhat.com/errata/RHSA-2026:3948
- https://access.redhat.com/security/cve/CVE-2026-2603
- https://bugzilla.redhat.com/show_bug.cgi?id=2440300
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-2603.json
- https://github.com/advisories/GHSA-x4p7-7chp-64hq
- https://nvd.nist.gov/vuln/detail/CVE-2026-2603
- https://github.com/keycloak/keycloak/issues/46911
- https://github.com/keycloak/keycloak/commit/8ed7e59dc08d79751a27c23aadb590f06b43f132
- https://github.com/keycloak/keycloak/pull/46932
- https://github.com/keycloak/keycloak/commit/4fd5367e6cc28cfa68fb2240fc459c12b1fdbf2a
- https://github.com/keycloak/keycloak/commits/26.5.5