CVE-2026-3872highCWE-601

CVE-2026-3872: high-severity vulnerability in Red Hat build of Keycloak 26.2

Keycloak: keycloak: information disclosure due to redirect_uri validation bypass

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21Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 7.3epss 0.4%
A flaw was found in Keycloak. This issue allows an attacker, who controls another path on the same web server, to bypass the allowed path in redirect Uniform Resource Identifiers (URIs) that use a wildcard. A successful attack may lead to the theft of an access token, resulting in information disclosure.
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:N
Affected products
Red Hat · Red Hat build of Keycloak 26.2Red Hat · Red Hat build of Keycloak 26.2.15Red Hat · Red Hat build of Keycloak 26.4Red Hat · Red Hat build of Keycloak 26.4.11
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