Keycloak-services: keycloak-services: ciba confidential-only contract not enforced for public clients
Summary
| CVE | CVE-2026-109082 |
|---|---|
| State | PUBLISHED |
| Assigner | redhat |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-10-12 07:16:36 UTC |
| Updated | 2026-10-12 08:17:19 UTC |
| Description | A flaw was found in the Client-Initiated Backchannel Authentication CIBA implementation within the keycloak-services component of Keycloak. This component handles advanced authentication flows where a client initiates a login on behalf of a user. The issue occurs because Keycloak fails to verify that a client is authorized to use the CIBA flow, allowing public clients to bypass security requirements. An attacker could use this flaw to trick a user into approving a login request, eventually gaining full access to the users account without needing a client secret. |
Risk And Classification
Primary CVSS: v3.1 6.8 MEDIUM from [email protected]
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N
Problem Types: CWE-287 | CWE-287 Improper Authentication
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 3.1 | [email protected] | Secondary | 6.8 | MEDIUM | CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N |
| 3.1 | CNA | CVSS | 6.8 | MEDIUM | CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N |
CVSS v3.1 Breakdown
Attack Vector
NetworkAttack Complexity
HighPrivileges Required
NoneUser Interaction
RequiredScope
UnchangedConfidentiality
HighIntegrity
HighAvailability
NoneCVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Red Hat | Red Hat Build Of Keycloak | Not specified | Not specified |
| CNA | Red Hat | Red Hat Build Of Keycloak | Not specified | Not specified |
| CNA | Red Hat | Red Hat Single Sign-On 7 | Not specified | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| bugzilla.redhat.com/show_bug.cgi | [email protected] | bugzilla.redhat.com | |
| access.redhat.com/security/cve/CVE-2026-109082 | [email protected] | access.redhat.com | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
Vendor Comments And Credit
Discovery Credit
CNA: Red Hat would like to thank MZOUGHI Mohamed Amine (zerOiQ) for reporting this issue. (en)
Additional Advisory Data
| Source | Time | Event |
|---|---|---|
| CNA | 2026-10-09T18:42:43.000Z | Reported to Red Hat. |
| CNA | 2026-10-09T18:42:43.000Z | Made public. |
Workarounds
CNA: 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.
There are currently no legacy QID mappings associated with this CVE.