Bug 2479565 (CVE-2026-8830)

Summary: CVE-2026-8830 keycloak: org.keycloak/keycloak-services: Keycloak: Policy bypass during WebAuthn credential registration via client-side JavaScript manipulation
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: aschwart, aszczucz, boliveir, drichtar, mposolda, pjindal, rmartinc, security-response-team, ssilvert, sthorger, vmuzikar
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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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.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description OSIDB Bzimport 2026-05-18 13:09:22 UTC
During WebAuthn credential registration, 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 allows a user to bypass administrative restrictions (e.g., algorithm requirements, user verification, or resident key configuration) by modifying client-side JavaScript during the registration process.