CVE-2026-9689
A flaw was found in Keycloak, an open-source identity and access management solution. When a client application is configured to accept broad redirect Uniform Resource Identifiers (URIs), a remote attacker can manipulate the authentication process by crafting a special web address. If a user clicks this link, the client application might incorrectly prioritize attacker-controlled information over legitimate data. This vulnerability, known as HTTP parameter pollution, could allow an attacker to bypass security measures or gain unauthorized access to resources.
Scoring
- Severity
- MEDIUM
- CVSS base score
- 4.2
- CVSS vector
- CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:N
- EPSS probability
- 0.32%
- CWE
- CWE-1288
- Published
- 2026-05-27
- Last modified
- 2026-08-20
Affected products
- Red Hat Red Hat build of Keycloak 26.4
- Red Hat Red Hat build of Keycloak 26.4
- Red Hat Red Hat build of Keycloak 26.6
- Red Hat Red Hat build of Keycloak 26.6
Weakness type
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