Vulnerabilities in pkg:maven/org.keycloak/keycloak-server
PACKAGECVE-2026-9796 is a MODERATE (CVSS 6.5) keycloak has a time-of-check time-of-use vulnerability (CWE-367: Time-of-check Time-of-use (TOCTOU) Race Condition) affecting Keycloak server libraries in the Maven ecosystem. The issue involves keycloak has a time-of-check time-of-use (toctou) race condition. Remediation is available by upgrading affected packages to version 26.6.4.
pkg:maven/org.keycloak/keycloak-server
Vulnerability advisories affecting package pkg:maven/org.keycloak/keycloak-server. Select an advisory below to view technical details or fixes.
| Advisory ID | CVE / NVD | Severity | Summary |
|---|---|---|---|
| GHSA-pq65-77rc-7r8c | CVE-2026-9796 | MODERATE | Keycloak has a Time-of-check Time-of-use (TOCTOU) Race Condition |
CVE-2026-9796 at a Glance
Security Impact
CVSS: 6.5
The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N).
How to Fix CVE-2026-9796
To remediate this vulnerability, upgrade all affected Keycloak server dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.
<dependency>
<groupId>org.keycloak</groupId>
<artifactId>keycloak-server</artifactId>
<version>26.6.4</version>
</dependency>Run the following command in your project directory to verify that all resolved dependencies use the patched release:
mvn dependency:tree -Dincludes=org.keycloakHow to Check if You Are Affected
To determine whether your Java application is affected by CVE-2026-9796, inspect your build dependencies using the Maven Dependency Plugin:
mvn dependency:tree -Dincludes=org.keycloakAnalyze the terminal output to locate any version of Keycloak server in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 26.6.4), your application is affected.
Note: The mvn dependency:tree -Dincludes=org.keycloak command inspects the resolved dependency graph declared in your project's POM files; it does not perform automated security scanning or inspect runtime dynamic classpaths. Always verify runtime container classpaths and shaded JARs.
Technical Details
Vulnerability Mechanism & Technical Analysis
This vulnerability is classified under CWE-367: Time-of-check Time-of-use (TOCTOU) Race Condition, where the product checks the state of a resource before using that resource, but the resource's state can change between the check and the use in a way that invalidates the results of the check. In Keycloak server, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.
Source Advisory Statement
CVE-2026-9796 Affected Keycloak server Versions
1 component(s)| Product / Package | Ecosystem | Affected Versions | Fixed Version |
|---|---|---|---|
|
org.keycloak:keycloak-server
|
Maven |
< 26.6.4
|
26.6.4
|
References
Frequently Asked Questions
What is CVE-2026-9796?
Which Keycloak server versions are affected?
What version fixes CVE-2026-9796?
Is keycloak-server affected?
What is the CVSS score of CVE-2026-9796?
What CWE is associated with CVE-2026-9796?
How can I check Maven dependencies for CVE-2026-9796?
Machine-readable OSV JSON
OSV v1.5 Schema
{
"schema_version" : "1.4.0",
"id" : "GHSA-pq65-77rc-7r8c",
"modified" : "2026-08-19T00:31:09Z",
"published" : "2026-05-28T06:31:09Z",
"aliases" : [ "CVE-2026-9796" ],
"summary" : "Keycloak has a Time-of-check Time-of-use (TOCTOU) Race Condition",
"details" : "A flaw was found in Keycloak. An authenticated administrator with the `manage-clients` role can exploit a Time-of-check to time-of-use (TOCTOU) vulnerability in the name-based admin role checks. This allows the attacker to escalate their privileges to `realm-admin` for all users within the realm, granting them extensive control over the system. The composite role relationship persists even after the attacker's own permissions are revoked and across system reboots.",
"severity" : [ {
"type" : "CVSS_V3",
"score" : "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N"
} ],
"affected" : [ {
"package" : {
"ecosystem" : "Maven",
"name" : "org.keycloak:keycloak-server"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "0"
}, {
"fixed" : "26.6.4"
} ]
} ]
} ],
"references" : [ {
"type" : "ADVISORY",
"url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-9796"
}, {
"type" : "WEB",
"url" : "https://github.com/keycloak/keycloak/issues/49427"
}, {
"type" : "WEB",
"url" : "https://github.com/keycloak/keycloak/pull/49624"
}, {
"type" : "WEB",
"url" : "https://github.com/keycloak/keycloak/commit/39cb8de54c8517efeda4baa8bc314fd40e9c6934"
}, {
"type" : "WEB",
"url" : "https://access.redhat.com/errata/RHSA-2026:56523"
}, {
"type" : "WEB",
"url" : "https://access.redhat.com/errata/RHSA-2026:56524"
}, {
"type" : "WEB",
"url" : "https://access.redhat.com/security/cve/CVE-2026-9796"
}, {
"type" : "WEB",
"url" : "https://bugzilla.redhat.com/show_bug.cgi?id=2482464"
}, {
"type" : "PACKAGE",
"url" : "https://github.com/keycloak/keycloak"
} ],
"database_specific" : {
"cwe_ids" : [ "CWE-367" ],
"severity" : "MODERATE",
"github_reviewed" : true,
"github_reviewed_at" : "2026-07-01T21:24:41Z",
"nvd_published_at" : "2026-05-28T05:16:41Z"
}
}