CVE-2026-7571
Keycloak: Access token disclosure and implicit flow bypass via forged client data
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.
How to fix CVE-2026-7571
To remediate CVE-2026-7571, upgrade the affected package to a fixed version below.
- —upgrade to 26.6.2 or later
Is CVE-2026-7571 being exploited?
No exploitation signal available. Neither CISA KEV nor a current EPSS score has been published for CVE-2026-7571.
Affected packages (1)
- from 0, < 26.6.2
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | HIGH7.1 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:N |