Flaw in Keycloak Allows Bypassing WebAuthn Policies
CVE-2026-8830

4.3MEDIUM

Key Information:

Vendor

Red Hat
Status
Red Hat Build Of Keycloak
Vendor
CVE Published:
19 May 2026

What is CVE-2026-8830?

A vulnerability identified in Keycloak allows authenticated users to bypass WebAuthn policies during credential registration through client-side JavaScript manipulation. The issue arises from the server-side processAction() not validating whether the new credential's parameters—such as public key algorithms—are compliant with the configured WebAuthn policies of the realm. This oversight could potentially facilitate the creation of credentials that do not meet the requisite administrative security standards, thereby undermining the system's overall security framework and permitting the usage of non-compliant authentication methods.

References

https://access.redhat.com/security/cve/CVE-2026-8830
vdb-entryx_refsource_REDHAT
https://bugzilla.redhat.com/show_bug.cgi?id=2479565
issue-trackingx_refsource_REDHAT

CVSS V3.1

Score:
4.3
Severity:
MEDIUM
Confidentiality:
None
Integrity:
Low
Availability:
None
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
Low
User Interaction:
None
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

Credit

Red Hat would like to thank Martin Bartoš (RedHat) for reporting this issue.
.