CVE-2026-18217

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.

CVSS v3 3.4 LOW

3.4^/10

CVSS v3 : LOW

Vector :

Exploitability : 1.6 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://access.redhat.com/security/cve/CVE-2026-18217	Vendor Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=2508311	Issue Tracking Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:redhat:build_of_keycloak:-:*:*:*:-:*:*:*

History

No history.

Information

Published : 2026-07-31 08:16

Updated : 2026-08-07 18:05

NVD link : CVE-2026-18217

Mitre link : CVE-2026-18217

CVE.ORG link : CVE-2026-18217

JSON object : View

Products Affected

redhat

build_of_keycloak

CWE

CWE-20

Improper Input Validation

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