Org.keycloak:keycloak services: Keycloak vulnerable to cross-site scripting (xss) via case-insensitive uri validation
Affects org.keycloak:keycloak-servicesSource GCVE Database
Not known to be exploited · CVSS 7.3 High : upgrade to 26.6.4 soon.
Data as of 29 Oct 2026, 17:10 UTC
- Patch
- Available – fixed in 26.6.4
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:NExploitation evidence
Disclosed: evidence found.
CVE published 25 Jun 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 29 Oct 2026.
What to do
Upgrade org.keycloak:keycloak-services to 26.6.4.
Patches and advisories
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| Mavenorg.keycloak:keycloak-services | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
Apply the official patch by upgrading Keycloak to version 26.6.4 or later. Red Hat has released security advisories and updated packages/images addressing this vulnerability. Before updating, back up existing installations and configurations. No other mitigations are specified or required beyond applying the official fix.
Description
Keycloak versions prior to 26.6.4 contain a cross-site scripting (XSS) vulnerability that allows a remote attacker with administrative privileges and specific permissions to bypass client URI validation. This is done by registering a malicious client with a specially crafted redirect URI using a case-insensitive javascript: or data: scheme. The vulnerability enables arbitrary code execution in the Keycloak origin when a victim interacts with crafted links, such as during logout or in the Admin Console. A fix is available in version 26.6.4.
References
- github.com/keycloak/keycloak/security/advisories/GHSA-v3f7-2p4r-mwfw (opens in a new tab)
- nvd.nist.gov/vuln/detail/CVE-2026-9086 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:30049 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:30050 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:30083 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:30084 (opens in a new tab)
- access.redhat.com/security/cve/CVE-2026-9086 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2480170 (opens in a new tab)
- github.com/keycloak/keycloak (opens in a new tab)
- security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-9086.json (opens in a new tab)