CVE-2026-7507: Keycloak Session Fixation Vulnerability
HIGHCVE-2026-7507 is a HIGH (CVSS 7.5) session fixation vulnerability (CWE-290: Authentication Bypass by Spoofing) affecting Keycloak libraries in the Maven ecosystem. The issue involves session fixation in oidc login flow that can lead to account takeover. Remediation is available by upgrading affected packages to version 26.6.2.
CVE-2026-7507 at a Glance
Security Impact
CVSS: 7.5
The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H).
How to Fix CVE-2026-7507
To remediate this vulnerability, upgrade all affected Keycloak 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-services</artifactId>
<version>26.6.2</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-2026-7507, inspect your build dependencies using the Maven Dependency Plugin:
mvn dependency:tree -Dincludes=org.keycloakAnalyze the terminal output to locate any version of Keycloak in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 26.6.2), 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-290: Authentication Bypass by Spoofing, where this attack-focused weakness is caused by incorrectly implemented authentication schemes that are subject to spoofing attacks. In Keycloak, 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-2026-7507 Affected Keycloak Versions
1 component(s)| Product / Package | Ecosystem | Affected Versions | Fixed Version |
|---|---|---|---|
|
org.keycloak:keycloak-services
|
Maven |
< 26.6.2
|
26.6.2
|
References
Frequently Asked Questions
What is CVE-2026-7507?
Which Keycloak versions are affected?
What version fixes CVE-2026-7507?
Is keycloak-services affected?
What is the CVSS score of CVE-2026-7507?
What CWE is associated with CVE-2026-7507?
How can I check Maven dependencies for CVE-2026-7507?
Machine-readable OSV JSON
OSV v1.5 Schema
{
"schema_version" : "1.4.0",
"id" : "GHSA-hf67-5vvq-fm3r",
"modified" : "2026-06-04T15:37:17Z",
"published" : "2026-05-19T12:31:42Z",
"aliases" : [ "CVE-2026-7507" ],
"summary" : "Keycloak: Session fixation in OIDC login flow that can lead to account takeover",
"details" : "A session fixation vulnerability was found in Keycloak's login-actions endpoints. An unauthenticated attacker could exploit this flaw by pre-creating an authentication session and tricking a victim into visiting a maliciously crafted link. By leveraging the /login-actions/restart endpoint—which processes session handles without adequate CSRF protection or cookie ownership validation—an attacker can reset the authentication flow state. This causes Single Sign-On (SSO) to authenticate the victim transparently upon clicking the link, allowing the attacker to hijack the required-action form without needing the victim's credentials. A successful exploit could lead to complete account takeover, including highly privileged administrative accounts.",
"severity" : [ {
"type" : "CVSS_V3",
"score" : "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H"
} ],
"affected" : [ {
"package" : {
"ecosystem" : "Maven",
"name" : "org.keycloak:keycloak-services"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "0"
}, {
"fixed" : "26.6.2"
} ]
} ]
} ],
"references" : [ {
"type" : "ADVISORY",
"url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-7507"
}, {
"type" : "WEB",
"url" : "https://github.com/keycloak/keycloak/pull/49134"
}, {
"type" : "WEB",
"url" : "https://github.com/keycloak/keycloak/commit/d791b270b9ea5203be40a9533c1c12c4d044fb52"
}, {
"type" : "WEB",
"url" : "https://access.redhat.com/errata/RHSA-2026:19594"
}, {
"type" : "WEB",
"url" : "https://access.redhat.com/errata/RHSA-2026:19595"
}, {
"type" : "WEB",
"url" : "https://access.redhat.com/errata/RHSA-2026:19596"
}, {
"type" : "WEB",
"url" : "https://access.redhat.com/errata/RHSA-2026:19597"
}, {
"type" : "WEB",
"url" : "https://access.redhat.com/security/cve/CVE-2026-7507"
}, {
"type" : "WEB",
"url" : "https://bugzilla.redhat.com/show_bug.cgi?id=2464145"
}, {
"type" : "PACKAGE",
"url" : "https://github.com/keycloak/keycloak"
}, {
"type" : "WEB",
"url" : "https://github.com/keycloak/keycloak/releases/tag/26.6.2"
} ],
"database_specific" : {
"cwe_ids" : [ "CWE-290" ],
"severity" : "HIGH",
"github_reviewed" : true,
"github_reviewed_at" : "2026-06-04T15:37:17Z",
"nvd_published_at" : "2026-05-19T12:16:19Z"
}
}