GHSA-g8vr-x4qh-25qg CVE-2026-8830
Keycloak: Policy bypass during WebAuthn credential registration via client-side JavaScript manipulation
- Severity
- 4.3 / 10
- Medium · CVSS 3.1
- Exploit chance (EPSS)
- 0.39%
- Chance of exploitation in the next 30 days. Higher than 33.33% of scored vulnerabilities.
- Known exploited
- No
- Not in CISA's catalog
- Weakness
- CWE-603 Use of Client-Side Authentication
- Fix
26.6.3- Upgrade org.keycloak:keycloak-services to this version or later
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 versions
Maven
| Package | Vulnerable | Fixed in |
|---|---|---|
| org.keycloak:keycloak-services | < 26.6.3 |
26.6.3 |
How to fix
Move to the fixed version or later with your package manager, update the lockfile, and run your tests. If the package only arrives through another dependency, upgrade that dependency first. If none of its releases pulls a fixed version yet, force the version with your package manager's override.
org.keycloak:keycloak-services Maven → 26.6.3
- maven
<dependency><groupId>org.keycloak</groupId><artifactId>keycloak-services</artifactId><version>26.6.3</version></dependency>- gradle
implementation("org.keycloak:keycloak-services:26.6.3")
Severity breakdown
CVSS 3.1 4.3
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- None
- Integrity
- Low
- Availability
- None
Weakness
CWE-603: Use of Client-Side Authentication
A client/server product performs authentication within client code but not in server code, allowing server-side authentication to be bypassed via a modified client that omits the authentication check.
How to prevent it
- Architecture and Design: Do not rely on client side data. Always perform server side authentication.
References
Advisories
Packages
Other links
- github.com/keycloak/keycloak/issues/49133
- github.com/keycloak/keycloak/pull/49344
- github.com/keycloak/keycloak/commit/47b9aef70948564151af85fd52e0d7e508c76490
- github.com/keycloak/keycloak/commit/d3da77ef363d698e7a74470ba52fcdce09e394c4
- access.redhat.com/errata/RHSA-2026:25097
- access.redhat.com/errata/RHSA-2026:25098
- access.redhat.com/errata/RHSA-2026:30049
- access.redhat.com/errata/RHSA-2026:30050
- access.redhat.com/security/cve/CVE-2026-8830
- bugzilla.redhat.com/show_bug.cgi
Timeline
- Published
- Last updated by the source
- Latest EPSS score
Related advisories
| Advisory | Severity | Why it's related |
|---|---|---|
| GHSA-v3f7-2p4r-mwfw Keycloak vulnerable to cross-site scripting (xss) via case-insensitive uri validation bypass | High | Also affects org.keycloak:keycloak-services |
| GHSA-9jrw-8xf7-xqhq Keycloak vulnerable to information disclosure through arbitrary filesystem path probing | Medium | Also affects org.keycloak:keycloak-services |
| GHSA-w3p3-7cjg-vgfw Keycloak allows unauthorized access to resources via uma permission ticket bypass | Medium | Also affects org.keycloak:keycloak-services |
| GHSA-f5p5-6xmx-p252 Keycloak vulnerable to authorization bypass via incorrect uri comparison | High | Also affects org.keycloak:keycloak-services |
| GHSA-r7rc-c989-86g6 Keycloak: Attacker can re-enable and take over disabled clients via registration access token | Medium | Also affects org.keycloak:keycloak-services |
| GHSA-4gv3-mc9p-5wqc Keycloak: Unauthenticated account takeover via reset-credentials flow bypass | Critical | Also affects org.keycloak:keycloak-services |
| GHSA-6g26-7cx5-mrrg Keycloak: Information disclosure due to user profile permission bypass | Low | Also affects org.keycloak:keycloak-services |
| GHSA-cpf7-j4cf-vqx4 Keycloak has an Out-of-bounds Read | Medium | Also affects org.keycloak:keycloak-services |
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