CVE-2026-9791 — Red Hat build of Keycloak 26.4

What is CVE-2026-9791?

A flaw was found in Keycloak. An authenticated user with existing organization membership can exploit this flaw by accessing user-facing APIs, such as the account API or by requesting an OpenID Connect (OIDC) token with the 'organization' scope. This allows organization metadata to be disclosed in tokens, even after an administrator has explicitly disabled the Organizations feature, potentially leading to incorrect authorization decisions by resource servers.

The record classifies CVE-2026-9791 under weakness class CWE-863. Its CVSS v3 base vector states that the flaw is reachable remotely over the network, needs low-privilege credentials, needs no user interaction. 4 affected-product entries are recorded, across 1 vendor, listed below. The identifier was first published 153 days ago.

Severity and exploitation probability

CVSS v3.1 base score: 4.3 — MEDIUM
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
EPSS (FIRST): 0.3% probability of exploitation in the next 30 days, higher than 29.1% of all scored CVEs
CISA KEV: Not listed in the CISA Known Exploited Vulnerabilities catalog
Threadlinqs priority: 3.3/10 — a Threadlinqs composite of the CVSS base score, the EPSS percentile and public exploit availability
Published: 2026-05-28, last modified 2026-06-26

Is CVE-2026-9791 being exploited?

It currently carries a trending score of 12 in the Threadlinqs vulnerability feed.

Affected products and versions

Red Hat: build of Keycloak 26.4, build of Keycloak 26.4.13, build of Keycloak 26.6, build of Keycloak 26.6.3

Affected software packages:

maven:org.keycloak:keycloak-server-spi-private — patched in 26.6.3
maven:org.keycloak:keycloak-services — patched in 26.6.3
maven:org.keycloak:keycloak-server-spi-private
maven:org.keycloak:keycloak-services

How to fix CVE-2026-9791

Fixed versions are recorded for 2 packages: maven:org.keycloak:keycloak-server-spi-private 26.6.3, maven:org.keycloak:keycloak-services 26.6.3. No vendor patch reference has been recorded for CVE-2026-9791 in the tracked sources. Follow the references below for a fix, and treat the products listed above as exposed until the vendor states otherwise.

Threat activity tracking CVE-2026-9791

1 tracked threat in the Threadlinqs corpus references CVE-2026-9791, either in the campaign’s CVE list or as an indicator on the campaign record.

CVE-2026-17059: Keycloak Admin REST API Broken Object-Level Authorization Exposes User PII — MEDIUM · 2026-07-31

Sources

Enriched from CVE.org, FIRST EPSS, GitHub Security Advisories. Last verified by Threadlinqs on 2026-10-10.