CVE-2026-18217

Full vulnerability record from the local CVENow database.
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.
Severity
MEDIUM
CVSS score
4.7 (v3.1)
Vulnerability status
Modified
Source identifier
[email protected]
Published
2026-07-31 08:16:28.037000
Last modified
2026-11-06 18:18:10.310000
View original CVE JSON
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  "id": "CVE-2026-18217",
  "sourceIdentifier": "[email protected]",
  "published": "2026-07-31T08:16:28.037",
  "lastModified": "2026-11-06T18:18:10.310",
  "vulnStatus": "Modified",
  "cveTags": [],
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    }
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