CVE-2026-8830

Keycloak: org.keycloak/keycloak-services: keycloak: policy bypass during webauthn credential registration via client-side javascript manipulation

MEDIUM
4.3
CVSS Score
Published: May 19, 2026 at 06:04 AM UTC
Updated: July 23, 2026 at 09:11 PM UTC
1 product affected across 1 vendorBuild of Keycloak

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Severity
MEDIUM4.3
Exploit prediction
EPSS 0.4%
SSVC
No known exploit

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

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

All versions26.4
Vendor states this is fixed in 26.4-19 (unaffected)
Vendor states this is fixed in 26.4.13 (unaffected)
Vendor states this is fixed in 26.4.13-1 (unaffected)
Vendor states this is fixed in 26.6-6 (unaffected)
Vendor states this is fixed in 26.6.3 (unaffected)
Vendor states this is fixed in 26.6.3-3 (unaffected)

References (6)

VDB Entryx_refsource_REDHATVendor Advisory
Source: cverecord
https://access.redhat.com/security/cve/CVE-2026-8830
Issue Trackingx_refsource_REDHATVendor Advisory
Source: cverecord
https://bugzilla.redhat.com/show_bug.cgi?id=2479565
Vendor Advisoryx_refsource_REDHAT
Source: cverecord
https://access.redhat.com/errata/RHSA-2026:25098
Vendor Advisoryx_refsource_REDHAT
Source: cverecord
https://access.redhat.com/errata/RHSA-2026:25097
Vendor Advisoryx_refsource_REDHAT
Source: cverecord
https://access.redhat.com/errata/RHSA-2026:30049
Vendor Advisoryx_refsource_REDHAT
Source: cverecord
https://access.redhat.com/errata/RHSA-2026:30050

SSVC — Action Prioritization

SSVCNo known exploitNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

4.3MEDIUMredhat
Attack Vector
NETWORK
Complexity
LOW
Privileges
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
LOW
Availability
NONE
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-603

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