low3.1
CVE-2026-4874
Keycloak Server-Side Request Forgery via OIDC token endpoint manipulation
Impact
A flaw was found in Keycloak. An authenticated attacker can perform Server-Side Request Forgery (SSRF) by manipulating the `client_session_host` parameter during refresh token requests. This occurs when a Keycloak client is configured to use the `backchannel.logout.url` with the `application.session.host` placeholder. Successful exploitation allows the attacker to make HTTP requests from the Keycloak server’s network context, potentially probing internal networks or internal APIs, leading to information disclosure.
Affected packages
| Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|
| maven | org.keycloak:keycloak-services | >= 26.5.0, < 26.6.3 | 26.6.3 |
Affected products
| Vendor | Product | Affected versions |
|---|---|---|
| Redhat | Build Of Keycloak | All versions |
| Redhat | Jboss Enterprise Application Platform | Version 8.0.0 |
| Redhat | Jboss Enterprise Application Platform Expansion Pack | All versions |
| Redhat | Single Sign-On | Version 7.0 |
Weakness classification
References
- NVD record
- CVE.org record
- GitHub advisory
- https://github.com/advisories/GHSA-22rm-wp4x-v5cx
- https://nvd.nist.gov/vuln/detail/CVE-2026-4874
- https://access.redhat.com/security/cve/CVE-2026-4874
- https://bugzilla.redhat.com/show_bug.cgi?id=2451611
- https://github.com/keycloak/keycloak/issues/47935
- https://github.com/keycloak/keycloak/pull/49682
- https://github.com/keycloak/keycloak/pull/49685
- https://github.com/keycloak/keycloak/commit/00dd0dd716c4319d3bac3eb2f2ac22d2a94f79fd
- https://github.com/keycloak/keycloak/commit/63de0efd351a7a684212a042a12271908f63f0ee
- https://access.redhat.com/errata/RHSA-2026:25097
- https://access.redhat.com/errata/RHSA-2026:25098
- https://access.redhat.com/errata/RHSA-2026:30049
- https://access.redhat.com/errata/RHSA-2026:30050