9.1

CVE-2026-16443: redhat build_of_keycloak

CVSS: 9.1v3.1CriticalAnalyzed
Published 05-08-2026Last modified 31-08-2026
Open JSON

Vulnerability summary

CVE-2026-16443 is a critical (CVSS 9.1) vulnerability in redhat build_of_keycloak. EPSS estimates a 0.26% chance of exploitation in the next 30 days, higher than 15.9% of scored vulnerabilities.

Overall risk
70/100
0100
High · default modelHow is this calculated?
CVSS score
9.1/10
010
Critical · v3.1 (NVD)
EPSS score
0.26%
0%100%
Low · +0.08 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 05-08-2026
    PublishedVulnerability first disclosed.
  2. 31-08-2026
    Last modifiedVulnerability information updated.

Description

A flaw was found in the SAML metadata import functionality of the keycloak-services component, which is the core engine for identity brokering in Red Hat Build of Keycloak. When importing identity provider metadata that lacks specific usage attributes for keys, the system incorrectly disables signature validation for SAML responses even if a signing certificate is provided. This issue allows an unauthenticated attacker to forge a SAML response and gain unauthorized access to a user account by knowing their external identifier.

CVSS metrics

2 scores · 2 sources · 1 version

EPSS trend

Probability

0.26%

Chance of exploitation in the next 30 days

Percentile

16%

Versus all other CVEs

30-day change

+0.08 pp

From 0.18% on 18-09-2026

18-09-202618-10-2026
EPSS score
0.26%

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

Redhat1 product

1 vendor · 1 product

References

6 links