CVE-2026-8830 is a medium-severity (CVSS 4.3) CWE-603 vulnerability in org.keycloak:keycloak-services. A fix is available for org.keycloak:keycloak-services — see the affected versions and patch details below.
Keycloak: Policy bypass during WebAuthn credential registration via client-side JavaScript manipulation
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-2026-8830.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
CVE-2026-8830 by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.
Where this sits among everything scored
Of 381,682 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-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 authenticated user can bypass configured WebAuthn policies during credential registration by manipulating client-side JavaScript. This occurs because the server-side processAction() fails to validate that the newly created credential's parameters, such as public key algorithms, match the realm's configured WebAuthn policies. This could lead to the creation of credentials that do not adhere to administrative security requirements, potentially weakening the overall security posture of the system by allowing non-compliant authentication methods.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| ☕Maven | org.keycloak:keycloak-services | all versions | 26.6.3org.keycloak:keycloak-services:26.6.3 |
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.
Fix
Update org.keycloak:keycloak-services to 26.6.3 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-8830 is resolved across your whole dependency graph.
Workarounds
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.
A Moderate security flaw was found in Keycloak's WebAuthn credential registration process. This issue allows an authenticated attacker to bypass configured WebAuthn policies, such as algorithm requirements or user verification, by manipulating client-side JavaScript during registration. This bypass could lead to the…
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.Source: Red Hat security advisory for CVE-2026-8830 (CC BY 4.0)
| Product | Fixed in | Advisory |
|---|---|---|
| Red Hat build of Keycloak 26.4 | rhbk/keycloak-operator-bundle:26.4.13-1 | RHSA-2026:30050 |
| Red Hat build of Keycloak 26.4.13 | rhbk/keycloak-rhel9-operator | RHSA-2026:30049 |
| Red Hat build of Keycloak 26.6 | rhbk/keycloak-operator-bundle:26.6.3-3 | RHSA-2026:25097 |
| Red Hat build of Keycloak 26.6.3 | rhbk/keycloak-rhel9-operator | RHSA-2026:25098 |
Frequently Asked Questions
Is CVE-2026-8830 in your dependencies?
Find it across Maven, including transitive dependencies.