CVE-2026-9689Keycloak: org.keycloak.protocol.oidc: http parameter pollution in oidc redirect uri allows response parameter duplication - #ghi-604
- 4.2MediumCVSS base score
- 0.32%Exploitation in 30 daysEPSS · top 74% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
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.
Timeline
ID reserved
By redhat
Published
- 3 months later
· 3 months later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| redhatCNA (assigner) | 3.1 | Medium4.2 | CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:N |
| NVDNVD · Modified | 3.1 | Medium4.2 | CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:N |
- EPSS (exploitation in 30 days)
- 0.32% · top 74% of all CVEs (13 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 4.2.
Affected products
Red Hat · Red Hat build of Keycloak 26.4
- unaffected 26.4.14-1 – < *
Red Hat · Red Hat build of Keycloak 26.4
- unaffected 26.4-22 – < *
Red Hat · Red Hat build of Keycloak 26.4
- unaffected 26.4-22 – < *
Red Hat · Red Hat build of Keycloak 26.4.14
All versions: unaffected
Red Hat · Red Hat build of Keycloak 26.6
- unaffected 26.6.5-1 – < *
Red Hat · Red Hat build of Keycloak 26.6
- unaffected 26.6-11 – < *
Red Hat · Red Hat build of Keycloak 26.6
- unaffected 26.6-11 – < *
Red Hat · Red Hat build of Keycloak 26.6.5
All versions: unaffected
Affected packages
From reviewed advisories of the GitHub Advisory Database.
- Mavenorg.keycloak:keycloak-servicesGHSA-wcvj-vpvw-9rr5 (opens in a new tab)
References
References6
- RHSA-2026:50846 (opens in a new tab)vendor-advisoryx_refsource_REDHAT
- RHSA-2026:50847 (opens in a new tab)vendor-advisoryx_refsource_REDHAT
- RHSA-2026:50848 (opens in a new tab)vendor-advisoryx_refsource_REDHAT
- RHSA-2026:50849 (opens in a new tab)vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/security/cve/CVE-2026-9689 (opens in a new tab)vdb-entryx_refsource_REDHAT
- RHBZ#2481845 (opens in a new tab)issue-trackingx_refsource_REDHAT
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2026-32212 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisory GHSA-wcvj-vpvw-9rr5 (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2026-9689)Record last updated .