CVE-2026-4874
An authenticated attacker can perform Server-Side Request Forgery (SSRF) by manipulating the `client_session_host` parameter during refresh token requests.
Does this matter?
Lower severity and a low EPSS score (0.29%). Track it; it rarely justifies an emergency change on its own.
Description
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.
- CVSS 3.1
- 3.1 LOWCVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:N
- EPSS
- 0.29% probability · 22th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-918
- Affected
- redhat/build of keycloak · redhat/jboss enterprise application platform · redhat/jboss enterprise application platform expansion pack · redhat/single sign-on
- Source
- secalert@redhat.com
References
- 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
- https://access.redhat.com/security/cve/CVE-2026-4874Vendor Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=2451611Issue Tracking, Vendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.