Description
A flaw was found in the SAML protocol implementation of Keycloak, an open-source identity and access management solution. The issue occurs when Keycloak handles SAML authentication requests using the HTTP-Redirect binding. If a client is configured with a wildcard redirect URL, an attacker can craft a request that includes malicious parameters. When a user authenticates, Keycloak appends its legitimate response to the attacker's parameters. This can cause some service providers to process the attacker's data instead of the real login information, potentially leading to a user being logged into the wrong account.
Affected products
redhat: build of keycloak
References6
Metrics
- CVSS 3.1
-
4.7
MEDIUM
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:N/I:L/A:N - EPSS — exploit probability
- 1% percentile: 45 · as of 13 November 2026
- CWE
- CWE-20
Could this be exploited in your environment?
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