Keycloak: offline session token dos

7.7 CVSS

Vulnerability Description

An unconstrained memory consumption vulnerability was discovered in Keycloak. It can be triggered in environments which have millions of offline tokens (> 500,000 users with each having at least 2 saved sessions). If an attacker creates two or more user sessions and then open the "consents" tab of the admin User Interface, the UI attempts to load a huge number of offline client sessions leading to excessive memory and CPU consumption which could potentially crash the entire system.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

No credits recorded in the NVD database.

References

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Affected Vendor

Red Hat

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Affected Software

Red Hat Single Sign-On 7.6 for RHEL 7, Red Hat Single Sign-On 7.6 for RHEL 8, Red Hat Single Sign-On 7.6 for RHEL 9, RHEL-8 based Middleware Containers, Single Sign-On 7.6.6, Red Hat Build of Keycloak

Vulnerable Versions:

0:18.0.11-2.redhat_00003.1.el7sso, 0:18.0.11-2.redhat_00003.1.el8sso, 0:18.0.11-2.redhat_00003.1.el9sso, 7.6-38, 7.6.6-2