4.9

CVE-2026-37978: redhat build_of_keycloak

CVSS: 4.9v3.1MediumAnalyzed
AliasesCGA-2jf2-8qgv-qjr4CGA-36vj-9233-ch8xCGA-3vpr-8qvc-4h7p
Published 19-05-2026Last modified 20-05-2026
Open JSON

Vulnerability summary

CVE-2026-37978 is a medium (CVSS 4.9) vulnerability in redhat build_of_keycloak. EPSS estimates a 0.46% chance of exploitation in the next 30 days, higher than 38.7% of scored vulnerabilities.

Overall risk
20/100
0100
Low · default modelHow is this calculated?
CVSS score
4.9/10
010
Medium · v3.1 (CVE.org)
EPSS score
0.46%
0%100%
Low · +0.06 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 19-05-2026
    PublishedVulnerability first disclosed.
  2. 20-05-2026
    Last modifiedVulnerability information updated.

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.

CVSS metrics

5 scores · 5 sources · 1 version

EPSS trend

Probability

0.46%

Chance of exploitation in the next 30 days

Percentile

39%

Versus all other CVEs

30-day change

+0.06 pp

From 0.40% on 21-09-2026

21-09-202621-10-2026
EPSS score
0.46%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Chainguard12 products
  • keycloak-26.4All versions (No fix recorded)
  • keycloak-26.4-iamguarded-compatAll versions (No fix recorded)
  • keycloak-26.5All versions (No fix recorded)
  • keycloak-26.5-iamguarded-compatAll versions (No fix recorded)
  • keycloak-fips-26.4All versions (No fix recorded)
Wolfi4 products
  • keycloak-26.4All versions (No fix recorded)
  • keycloak-26.4-iamguarded-compatAll versions (No fix recorded)
  • keycloak-26.5All versions (No fix recorded)
  • keycloak-26.5-iamguarded-compatAll versions (No fix recorded)
Org.keycloak1 product
  • keycloak-services< 26.6.2
Redhat1 product

4 vendors · 18 products

References

8 links