CVE-2026-9689 is a medium-severity (CVSS 4.2) CWE-1288 vulnerability in org.keycloak:keycloak-services. No vendor fix is recorded yet; mitigation options are listed below.
Keycloak Services has Improper Validation of Consistency within Input
Exploitation Status
No confirmed exploitation observed yet
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-9689.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
CVE-2026-9689 by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.
Where this sits among everything scored
Of 384,534 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Counts from FIRST.org, log-scaled.
Real-World Exposure
org.keycloak:keycloak-services☕org.keycloak:keycloak-servicesReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Maven packages — download data is not available via public APIs for these ecosystems.
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 Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| ☕Maven | org.keycloak:keycloak-services | ≥ 26.5.0 | No fix |
| ☕Maven | org.keycloak:keycloak-services | all versions | No fix |
Affected Products
build of keycloakredhatDetection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for org.keycloak:keycloak-services, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Remediation status
No patched version of org.keycloak:keycloak-services has shipped for CVE-2026-9689 yet. Where your build allows, override or pin the dependency away from the vulnerable range, and apply any maintainer-recommended mitigation.
Mitigate without a patch
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
Fixing This On Your OS
If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.
This Moderate severity flaw in Keycloak arises from HTTP parameter pollution when a client is configured with a wildcard redirect URI. An attacker could craft a malicious authorization URL that, if clicked by a user, may lead to the client application incorrectly processing attacker-controlled OIDC response…
| Product | Fixed in | Advisory |
|---|---|---|
| Red Hat build of Keycloak 26.4 | rhbk/keycloak-operator-bundle:26.4.14-1 | RHSA-2026:50847 |
| Red Hat build of Keycloak 26.4.14 | rhbk/keycloak-rhel9 | RHSA-2026:50846 |
| Red Hat build of Keycloak 26.6 | rhbk/keycloak-operator-bundle:26.6.5-1 | RHSA-2026:50849 |
| Red Hat build of Keycloak 26.6.5 | see advisory | RHSA-2026:50848 |
Frequently Asked Questions
Is CVE-2026-9689 in your dependencies?
Find it across Maven, including transitive dependencies.