High severity7.7NVD Advisory· Published Dec 14, 2023· Updated Jun 17, 2026
CVE-2023-6563
CVE-2023-6563
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.
AI Insight
LLM-synthesized narrative grounded in this CVE's description and references.
Affected packages
Versions sourced from the GitHub Security Advisory.
| Package | Affected versions | Patched versions |
|---|---|---|
org.keycloak:keycloak-model-jpaMaven | < 21.0.0 | 21.0.0 |
Affected products
16- cpe:/a:redhat:build_keycloak:
cpe:/a:redhat:red_hat_single_sign_on:7.6.6+ 5 more
- cpe:/a:redhat:red_hat_single_sign_on:7.6.6
- cpe:/a:redhat:red_hat_single_sign_on:7.6::el7range: 0:18.0.11-2.redhat_00003.1.el7sso
- cpe:/a:redhat:red_hat_single_sign_on:7.6::el8range: 0:18.0.11-2.redhat_00003.1.el8sso
- cpe:/a:redhat:red_hat_single_sign_on:7.6::el9range: 0:18.0.11-2.redhat_00003.1.el9sso
- cpe:2.3:a:redhat:single_sign-on:-:*:*:*:text-only:*:*:*
- cpe:2.3:a:redhat:single_sign-on:7.6:*:*:*:*:*:*:*
- Red Hat/RHEL-8 based Middleware Containersv5cpe:/a:redhat:rhosemc:1.0::el8Range: 7.6.6-2
cpe:2.3:a:redhat:openshift_container_platform:4.11:*:*:*:*:*:*:*+ 3 more
- cpe:2.3:a:redhat:openshift_container_platform:4.11:*:*:*:*:*:*:*
- cpe:2.3:a:redhat:openshift_container_platform:4.12:*:*:*:*:*:*:*
- cpe:2.3:a:redhat:openshift_container_platform_for_power:4.10:*:*:*:*:*:*:*
- cpe:2.3:a:redhat:openshift_container_platform_for_power:4.9:*:*:*:*:*:*:*
cpe:2.3:a:redhat:openshift_container_platform_for_ibm_linuxone:4.10:*:*:*:*:*:*:*+ 1 more
- cpe:2.3:a:redhat:openshift_container_platform_for_ibm_linuxone:4.10:*:*:*:*:*:*:*
- cpe:2.3:a:redhat:openshift_container_platform_for_ibm_linuxone:4.9:*:*:*:*:*:*:*
Patches
Vulnerability mechanics
References
12- access.redhat.com/errata/RHSA-2023:7857nvdExploitWEB
- access.redhat.com/errata/RHSA-2023:7854nvdVendor AdvisoryWEB
- access.redhat.com/errata/RHSA-2023:7855nvdVendor AdvisoryWEB
- access.redhat.com/errata/RHSA-2023:7856nvdVendor AdvisoryWEB
- access.redhat.com/errata/RHSA-2023:7858nvdVendor AdvisoryWEB
- access.redhat.com/security/cve/CVE-2023-6563nvdVendor AdvisoryWEB
- github.com/advisories/GHSA-54f3-c6hg-865hghsaADVISORY
- nvd.nist.gov/vuln/detail/CVE-2023-6563ghsaADVISORY
- bugzilla.redhat.com/show_bug.cginvdIssue TrackingWEB
- github.com/keycloak/keycloak/commit/556146f961f7c8ddf64de15e2117a58d045f72b5ghsaWEB
- github.com/keycloak/keycloak/issues/13340nvdIssue TrackingWEB
- github.com/keycloak/keycloak/pull/15463ghsaWEB
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