7.3

CVE-2026-9086: redhat build_of_keycloak Cross-site Scripting

CVSS: 7.3v3.1HighAnalyzed
Published 25-06-2026Last modified 15-07-2026
Open JSON

Vulnerability summary

CVE-2026-9086 is a high (CVSS 7.3) Cross-site Scripting vulnerability in redhat build_of_keycloak. EPSS estimates a 0.78% chance of exploitation in the next 30 days, higher than 55.1% of scored vulnerabilities.

Overall risk
29/100
0100
Medium · default modelHow is this calculated?
CVSS score
7.3/10
010
High · v3.1 (CVE.org)
EPSS score
0.78%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 25-06-2026
    PublishedVulnerability first disclosed.
  2. 15-07-2026
    Last modifiedVulnerability information updated.

Description

A flaw was found in Keycloak. A remote attacker with administrative privileges, specifically those with `manage-client` permission or access to client registration endpoints, could bypass client Uniform Resource Identifier (URI) validation. This is achieved by registering a malicious client with a specially crafted redirect URI using a case-insensitive `javascript:` or `data:` scheme. This Cross-Site Scripting (XSS) vulnerability allows for arbitrary code execution in the Keycloak origin when a victim clicks the crafted link, such as in the logout flow or the Admin Console.

CVSS metrics

2 scores · 2 sources · 1 version

EPSS trend

Probability

0.78%

Chance of exploitation in the next 30 days

Percentile

55%

Versus all other CVEs

30-day change

0.00 pp

From 0.78% on 19-09-2026

19-09-202619-10-2026
EPSS score
0.78%

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

7 links