Description
A flaw was found in Keycloak, an open-source identity and access management solution. When a client application is configured to accept broad redirect Uniform Resource Identifiers (URIs), a remote attacker can manipulate the authentication process by crafting a special web address. If a user clicks this link, the client application might incorrectly prioritize attacker-controlled information over legitimate data. This vulnerability, known as HTTP parameter pollution, could allow an attacker to bypass security measures or gain unauthorized access to resources.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Red Hat | Red Hat build of Keycloak 26.4 | — | — |
| Red Hat | Red Hat build of Keycloak 26.4.14 | — | — |
| Red Hat | Red Hat build of Keycloak 26.6 | — | — |
| Red Hat | Red Hat build of Keycloak 26.6.5 | — | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Wolfi
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Wolfi rolling | keycloak-26.5 +2 | No fix yet | — |
| Wolfi rolling | keycloak-26.6 +1 | 26.6.6-r0 | — |
Affected packages
| Ecosystem | Package | Affected | Fixed | Record |
|---|---|---|---|---|
| Maven | org.keycloak:keycloak-services | >= 26.5.0, <= 26.6.4 | — | GHSA-wcvj-vpvw-9rr5 |
| Maven | org.keycloak:keycloak-services | <= 26.4.7 | — | GHSA-wcvj-vpvw-9rr5 |
Advisories 1
- WID-SEC-2026-1708 Keycloak: Mehrere Schwachstellen BSI CERT-Bund (WID) · Nov 8, 2026
References
- RHSA-2026:50846 vendor-advisory
- RHSA-2026:50847 vendor-advisory
- RHSA-2026:50848 vendor-advisory
- RHSA-2026:50849 vendor-advisory
- https://access.redhat.com/security/cve/CVE-2026-9689 vdb-entry
- RHBZ#2481845 issue-tracking