Keycloak: keycloak: brute-force protection bypass in ciba flow
Priority LOW 20CWE-305Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- Required
- Attack complexity
- Low
- Impact type
- —
- Confidentiality · integrity · availability
- Low · None · None
- Fix status
- Fixed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA, GitHub and Red Hat.
Summary
A flaw was found in Keycloak, an open-source identity and access management solution. When a user account is temporarily locked due to repeated failed login attempts, an attacker with valid client credentials can exploit the Client-Initiated Backchannel Authentication (CIBA) flow to bypass this brute-force protection. This allows continued authentication attempts and token issuance even when the account should be locked, potentially enabling further unauthorized access attempts.
Why it matters now
Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00375 31st percentileScored 2026-11-07
Fix Fixed Red Hat: 4 advisories
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Red Hat | Red Hat build of Keycloak 26.4 | — | 26.4.14-1 | Patch available | CNA |
| Red Hat | Red Hat build of Keycloak 26.4 | — | 26.4-22 | Patch available | CNA |
| Red Hat | Red Hat build of Keycloak 26.4 | — | 26.4-22 | Patch available | CNA |
| Red Hat | Red Hat build of Keycloak 26.4.14 | — | — | Not affected | CNA |
| Red Hat | Red Hat build of Keycloak 26.6 | — | 26.6.5-1 | Patch available | CNA |
| Red Hat | Red Hat build of Keycloak 26.6 | — | 26.6-11 | Patch available | CNA |
| Red Hat | Red Hat build of Keycloak 26.6 | — | 26.6-11 | Patch available | CNA |
| Red Hat | Red Hat build of Keycloak 26.6.5 | — | — | Not affected | CNA |
| — | org.keycloak:keycloak-services (Maven) | up to 26.4.7 | — | No fix listed | GHSA-q6h7-xxp7-7429 |
| — | org.keycloak:keycloak-services (Maven) | 26.5.0 – 26.6.4 | — | No fix listed | GHSA-q6h7-xxp7-7429 |
- Red Hat build of Keycloak 26.4 VendorRed Hat Affected — Fixed in 26.4.14-1 Patch available CNA
- Red Hat build of Keycloak 26.4 VendorRed Hat Affected — Fixed in 26.4-22 Patch available CNA
- Red Hat build of Keycloak 26.4 VendorRed Hat Affected — Fixed in 26.4-22 Patch available CNA
- Red Hat build of Keycloak 26.4.14 VendorRed Hat Affected — Fixed in — Not affected CNA
- Red Hat build of Keycloak 26.6 VendorRed Hat Affected — Fixed in 26.6.5-1 Patch available CNA
- Red Hat build of Keycloak 26.6 VendorRed Hat Affected — Fixed in 26.6-11 Patch available CNA
- Red Hat build of Keycloak 26.6 VendorRed Hat Affected — Fixed in 26.6-11 Patch available CNA
- Red Hat build of Keycloak 26.6.5 VendorRed Hat Affected — Fixed in — Not affected CNA
- org.keycloak:keycloak-services (Maven) Vendor— Affected up to 26.4.7 Fixed in — No fix listed GHSA-q6h7-xxp7-7429
- org.keycloak:keycloak-services (Maven) Vendor— Affected 26.5.0 – 26.6.4 Fixed in — No fix listed GHSA-q6h7-xxp7-7429
Remediation
Red Hat 4 advisories
- RHSA-2026:50849 Released 2026-08-05 · Red Hat rating ImportantRed Hat build of Keycloak 26.6.5 Images Security Update
- Red Hat build of Keycloak 26.6 rhbk/keycloak-operator-bundle, rhbk/keycloak-rhel9, rhbk/keycloak-rhel9-operator
- RHSA-2026:50847 Released 2026-08-05 · Red Hat rating ImportantRed Hat build of Keycloak 26.4.14 Images Security Update
- Red Hat build of Keycloak 26.4 rhbk/keycloak-operator-bundle, rhbk/keycloak-rhel9, rhbk/keycloak-rhel9-operator
- RHSA-2026:50846 Released 2026-08-05 · Red Hat rating ImportantRed Hat build of Keycloak 26.4.14 Security Update
- Red Hat build of Keycloak 26.4.14
Show 1 more Red Hat advisories
- RHSA-2026:50848 Released 2026-08-05 · Red Hat rating ImportantRed Hat build of Keycloak 26.6.5 Security Update
- Red Hat build of Keycloak 26.6.5
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat build of Keycloak 26.4 | Fixed | RHSA-2026:50847 |
| Red Hat build of Keycloak 26.4.14 | Fixed | RHSA-2026:50846 |
| Red Hat build of Keycloak 26.6 | Fixed | RHSA-2026:50849 |
| Red Hat build of Keycloak 26.6.5 | Fixed | RHSA-2026:50848 |
Timeline
- 2026-10-02 Threatist record created from CVE-2026-9798
- 2026-10-03 Alias added: GHSA-q6h7-xxp7-7429
References
Advisory 7
Other 8
- https://github.com/keycloak/keycloak/issues/49432
- https://github.com/keycloak/keycloak/pull/49791
- https://github.com/keycloak/keycloak/pull/49903
- https://github.com/keycloak/keycloak/pull/49905
- https://github.com/keycloak/keycloak/commit/11c2695064cd93da1d333df3f69d4a4141e86c29
- https://github.com/keycloak/keycloak/commit/2edc6b112e2dedce63062b89ab3c7ae542e0d9ac
- https://github.com/keycloak/keycloak/commit/a11e3254efc16ae72ce5092b93b9f557a4ba43ae
- https://github.com/keycloak/keycloak
More Red Hat Build Of Keycloak vulnerabilities
- TI-2026-02223 Keycloak: keycloak: unauthorized authentication via disabled saml identity provider CVSS 3.1HIGH 8.1
- TI-2024-01049 Keycloak: path transversal in redirection validation CVSS 3.1HIGH 8.1
- TI-2026-13740 Keycloak-services: keycloak-services: saml idp-initiated broker login bypasses link-only restriction CVSS 3.1CRITICAL 9.8
- TI-2026-13741 Keycloak-services: keycloak-services: saml broker metadata import disables response signature validation CVSS 3.1CRITICAL 9.1
- TI-2026-13106 Keycloak-services: keycloak-services: dcr protocol mapper type-swap policy bypass allows privilege escalation CVSS 3.1HIGH 8.8
- TI-2026-02631 Authentication bypass in Red Hat build of Keycloak 26.2 CVSS 3.1HIGH 8.8
Sources
- CVE-2026-9798 · CVE Program
- CVE-2026-9798 · NVD
- FIRST EPSS
- GHSA-q6h7-xxp7-7429 · GitHub Advisory Database · CC BY 4.0
- CVE-2026-9798 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences