CVE-2026-7571 Keycloak: keycloak: access token disclosure and implicit flow bypass via forged client data
Attackers can bypass implicit flow restrictions to obtain unauthorized access tokens, leading to token disclosure in logs and headers.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-7571?
CVE-2026-7571 is a high-severity vulnerability in Redhat Build of Keycloak, published on 19 May 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
A flaw was found in Keycloak. A low-privilege user, with knowledge of user credentials and client ID, can bypass a security control intended to disable the implicit flow in OpenID Connect (OIDC) clients. By manipulating client data during a session restart, an attacker can obtain an access token that should not be available. This vulnerability can also lead to the exposure of these access tokens in server logs, proxy logs, and HTTP Referrer headers, resulting in sensitive information disclosure.
Weakness: CWE-472
Which versions are affected by CVE-2026-7571?
3 open source packages ship an affected version, including org.keycloak:keycloak-services and keycloak. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
org.keycloak:keycloak-services Maven | All versions | 26.6.2 |
org.keycloak:keycloak-services Maven | All versions | 26.6.2 |
keycloak Bitnami | From 26.4.0 | 26.4.12 |
Products include Redhat Build of Keycloak.
How do I fix CVE-2026-7571?
Upgrade org.keycloak:keycloak-services to 26.6.2 or later.
Is CVE-2026-7571 being exploited?
There is no known exploitation of CVE-2026-7571 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 BIT-keycloak-2026-7571, ECHO-3445-2751-481d, GHSA-hq3p-w4xv-x7vp, MINI-978x-fgfc-8388, MINI-xvfj-j6fw-m8vj.