CVE-2026-7571
Keycloak: keycloak: access token disclosure and implicit flow bypass via forged client data
CVSS Score
7.1
EPSS Score
0.0%
EPSS Percentile
8th
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.
| CWE | CWE-472 |
| Vendor | red hat |
| Product | red hat build of keycloak 26.4 |
| Published | May 19, 2026 |
| Last Updated | May 20, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:N Attack Vector
Network
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
Low
Availability
None
Affected Versions
Red Hat / Red Hat build of Keycloak 26.4
All versions affected Red Hat / Red Hat build of Keycloak 26.4
All versions affected Red Hat / Red Hat build of Keycloak 26.4
All versions affected Red Hat / Red Hat build of Keycloak 26.4.12
All versions affected References
Credits
Red Hat would like to thank Evan Hendra for reporting this issue.