CVE-2026-37978

Name: CVE-2026-37978
Creator: NVD / NIST
Published: 2026-05-19T12:16:17.54+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 4.9/10EPSS 0.40%

Last modified Jun 17, 2026

CVE-2026-37978 is a medium-severity vulnerability rated 4.9/10 on the CVSS scale. A flaw was found in Keycloak. A low-privilege administrator with the 'view-clients' role can exploit this by invoking the 'evaluate-scopes' Admin API endpoints with an arbitrary user ID (userId) parameter. EPSS estimates a 0.40% chance of exploitation in the next 30 days.

Description

A flaw was found in Keycloak. A low-privilege administrator with the 'view-clients' role can exploit this by invoking the 'evaluate-scopes' Admin API endpoints with an arbitrary user ID (userId) parameter. This vulnerability allows for cross-role personally identifiable information (PII) leakage, enabling unauthorized visibility into user identities and authorizations across the realm. Exploitation is possible remotely via network access to the Admin API.

Metrics

CVSS 3.1

4.9/10

CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N

EPSS Probability

0.40%

31.6th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-639

Affected Software

Vendor	Product	Versions
Redhat	Build Of Keycloak	< 26.4.12

References

https://access.redhat.com/errata/RHSA-2026:19596Vendor Advisory
https://access.redhat.com/errata/RHSA-2026:19597Vendor Advisory
https://access.redhat.com/security/cve/CVE-2026-37978Vendor Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=2455327Vendor Advisory

Timeline

Published: May 19, 2026
Last Modified: Jun 17, 2026
Status: Analyzed

Frequently Asked Questions

What is CVE-2026-37978?

How severe is CVE-2026-37978?

CVE-2026-37978 has a CVSS score of 4.9/10 (MEDIUM severity). The EPSS model estimates a 0.40% probability of exploitation in the next 30 days.

How do I fix CVE-2026-37978?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2026-37978?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST