Review reviewHigh

CVE-2026-3872

Red Hat Red Hat build of Keycloak 26.2, Red Hat build of Keycloak 26.2.15, Red Hat build of Keycloak 26.4

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: 7.3
EPSS: 0.44%
CISA KEV: Not listed
Published: 2026.04.02

PRIORITY ASSESSMENT

Review review

The CVSS severity warrants an early asset and exposure review.

Known exploitationNot established by KEV

Exploit probability0.44%

Technical severityCVSS 7.3

Vulnerability overview

Affected product and versions

Product: Red Hat Red Hat build of Keycloak 26.2, Red Hat build of Keycloak 26.2.15, Red Hat build of Keycloak 26.4
Affected versions: 26.2, 26.2.15, 26.4, 26.4.11
Fixed versions: No verified fixed-version field is available yet

Recommended response sequence

Confirm exposure before applying a vendor-supported change.

Full remediation guide

1
Identify
Confirm that Red Hat Red Hat build of Keycloak 26.2, Red Hat build of Keycloak 26.2.15, Red Hat build of Keycloak 26.4 and an affected version are present.
2
Prioritize
Combine exploitation signals with asset exposure and business criticality.
3
Remediate
Follow the vendor advisory or supported update path and preserve rollback options.
4
Verify
Recheck the version, service health, access paths, and relevant logs.

Technical data

CVSS vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:N
CWE: CWE-601