CVE-2026-9798 Keycloak: keycloak: brute-force protection bypass in ciba flow
Attackers with valid client credentials can bypass brute-force protection in Keycloak's CIBA flow, allowing continued authentication attempts on locked accounts.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2026-9798?
CVE-2026-9798 is a medium-severity vulnerability in Redhat Build of Keycloak, published on 28 May 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official description
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.
Weakness: CWE-305
Which versions are affected by CVE-2026-9798?
4 open source packages ship an affected version, including org.keycloak:keycloak-services. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
org.keycloak:keycloak-services Maven | All versions to 26.4.7 | None |
org.keycloak:keycloak-services Maven | All versions to 26.4.7 | None |
org.keycloak:keycloak-services Maven | From 26.5.0 to 26.6.4 | None |
org.keycloak:keycloak-services Maven | From 26.5.0 to 26.6.4 | None |
Products include Redhat Build of Keycloak.
How do I fix CVE-2026-9798?
Upgrade to a fixed version.
Is CVE-2026-9798 being exploited?
There is no known exploitation of CVE-2026-9798 in the wild and no public exploit code.
Other vulnerabilities in Redhat Build of Keycloak
- CVE-2026-15572 Keycloak-services: keycloak-services: dcr protocol mapper type-swap policy bypass allows privilege escalation
- CVE-2026-3047 Keycloak SAML Broken has Authentication Bypass by Primary Weakness
- CVE-2026-15573 Keycloak-services: keycloak-services: authorization bypass via unnormalized uri matching in pathmatcher
- CVE-2026-16102 Keycloak-services: keycloak-services: default dcr policy allows role forgery via user property mappers
- CVE-2026-1609 Org.keycloak/keycloak-quarkus-server: keycloak: unauthorized access via jwt authorization grant with disabled users
Sources
Also known as ECHO-3050-e6f8-f8c9, GHSA-q6h7-xxp7-7429, MINI-5gpf-x72p-7j86, MINI-wppf-qw6v-37vx.