CVE-2026-7571

HIGH

Keycloak: keycloak: access token disclosure and implicit flow bypass via forged client data

Title source: cna
STIX 2.1

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.

References (4)

Core 4
Core References
Vdb Entry, X_Refsource_Redhat vdb-entry x_refsource_redhat
https://access.redhat.com/security/cve/CVE-2026-7571
Issue Tracking, X_Refsource_Redhat issue-tracking x_refsource_redhat
RHBZ#2464263
https://bugzilla.redhat.com/show_bug.cgi?id=2464263
Vendor Advisory vendor-advisory x_refsource_redhat
RHSA-2026:19596
https://access.redhat.com/errata/RHSA-2026:19596
Vendor Advisory vendor-advisory x_refsource_redhat
RHSA-2026:19597
https://access.redhat.com/errata/RHSA-2026:19597

Scores

CVSS v3 7.1
EPSS 0.0001
EPSS Percentile 1.5%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:N

CISA SSVC

Vulnrichment
Exploitation none
Automatable no
Technical Impact partial

Details

CWE
CWE-472
Status published
Products (4)
Red Hat/Red Hat Build of Keycloak
Red Hat/Red Hat build of Keycloak 26.4 26.4-17
Red Hat/Red Hat build of Keycloak 26.4 26.4.12-1
Red Hat/Red Hat build of Keycloak 26.4.12
Published May 19, 2026
Tracked Since May 19, 2026