What’s Vulnerable › Vulnerabilities

CVE-2026-37981: Keycloak: org.keycloak.authorization: keycloak: information disclosure via broken access control in user lookup endpoint

• Severity: medium (CVSS 4.3 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.4% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-05-19 · updated 2026-10-26
• Weakness: CWE-1220

Description

A flaw was found in Keycloak. A broken access control vulnerability in the Account Resources user lookup endpoint allows a remote authenticated user, who owns at least one User-Managed Access (UMA) resource, to enumerate and harvest personally identifiable information (PII) for all realm users. By sending crafted requests with arbitrary usernames or email values, the endpoint returns full profile objects for unrelated users. This leads to broad profile-level information disclosure.

Affected products

• Red Hat build of Keycloak 26.4: from 26.4 before 26.4.12 — fixed in 26.4.12

How to fix

Upgrade to a fixed version: Red Hat build of Keycloak 26.4 26.4.12. Check the vendor advisory for mitigations.

References

• https://access.redhat.com/errata/RHSA-2026:19596
• https://access.redhat.com/errata/RHSA-2026:19597
• https://access.redhat.com/security/cve/CVE-2026-37981
• https://bugzilla.redhat.com/show_bug.cgi?id=2455326

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