CVE-2026-9689Keycloak: org.keycloak.protocol.oidc: http parameter pollution in oidc redirect uri allows response parameter duplication - #ghi-604
Updated under an hour ago ()
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It affects Red Hat build of Keycloak 26.4 and 1 other product. Add what you run to find out whether that includes you.
No exploitation reported and no EPSS estimate yet.
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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.
- CVSS
- 4.2 MEDIUM (v3.1, CNA)CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:N
- Weakness (CWE)
- CWE-1288
- Known exploited
- Not in CISA's KEV catalog
- EPSS (exploitation in the next 30 days)
- Not loaded for this CVE
- Assigned by
- redhat
- NVD analysis
- Modified
- Record last updated
- Aug 19, 2026
- First seen by InfoSec Signals
- Oct 9, 2026
Affected products
Red Hat Red Hat build of Keycloak 26.4 redhat:build_keycloak | from 26.4.14-1 not affected | CNA record |
redhat build_of_keycloak redhat:build_of_keycloak | all versions | NVD |
References
- https://access.redhat.com/errata/RHSA-2026:50846vendor-advisory, x-refsource-redhat
- https://access.redhat.com/errata/RHSA-2026:50847vendor-advisory, x-refsource-redhat
- https://access.redhat.com/errata/RHSA-2026:50848vendor-advisory, x-refsource-redhat
- https://access.redhat.com/errata/RHSA-2026:50849vendor-advisory, x-refsource-redhat
- https://access.redhat.com/security/cve/CVE-2026-9689vdb-entry, x-refsource-redhat, vendor-advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=2481845issue-tracking, x-refsource-redhat, vendor-advisory
The CVE record on cve.org NVD's entry
The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.