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When metrics are enabled, the system records raw error messages from failed account operations as Prometheus metric labels. Because these error messages can include user-supplied input like nonexistent client IDs, an authenticated user can create a massive number of unique metric entries, eventually exhausting system memory and causing the service to crash or become unavailable."}],"affected":[{"vendor":"Red Hat","product":"Red Hat build of Keycloak 26.6","collectionURL":"https://catalog.redhat.com/software/containers/","packageName":"rhbk/keycloak-operator-bundle","defaultStatus":"affected","versions":[{"version":"26.6.5-1","lessThan":"*","versionType":"rpm","status":"unaffected"}],"cpes":["cpe:/a:redhat:build_keycloak:26.6::el9"]},{"vendor":"Red Hat","product":"Red Hat build of Keycloak 26.6","collectionURL":"https://catalog.redhat.com/software/containers/","packageName":"rhbk/keycloak-rhel9","defaultStatus":"affected","versions":[{"version":"26.6-11","lessThan":"*","versionType":"rpm","status":"unaffected"}],"cpes":["cpe:/a:redhat:build_keycloak:26.6::el9"]},{"vendor":"Red Hat","product":"Red Hat build of Keycloak 26.6","collectionURL":"https://catalog.redhat.com/software/containers/","packageName":"rhbk/keycloak-rhel9-operator","defaultStatus":"affected","versions":[{"version":"26.6-11","lessThan":"*","versionType":"rpm","status":"unaffected"}],"cpes":["cpe:/a:redhat:build_keycloak:26.6::el9"]},{"vendor":"Red Hat","product":"Red Hat build of Keycloak 26.6.5","collectionURL":"https://access.redhat.com/downloads/content/package-browser/","defaultStatus":"unaffected","packageName":"keycloak-services","cpes":["cpe:/a:redhat:build_keycloak:26.6::el9"]},{"vendor":"Red Hat","product":"Red Hat build of Keycloak 26.6.5","collectionURL":"https://access.redhat.com/downloads/content/package-browser/","defaultStatus":"unaffected","packageName":"rhbk-keycloak-rhel9/rhbk-keycloak-rhel9","cpes":["cpe:/a:redhat:build_keycloak:26.6::el9"]},{"vendor":"Red Hat","product":"Red Hat build of Keycloak 26.6.5","collectionURL":"https://access.redhat.com/downloads/content/package-browser/","defaultStatus":"unaffected","packageName":"rhbk-openshift-rhel9/rhbk-openshift-rhel9","cpes":["cpe:/a:redhat:build_keycloak:26.6::el9"]},{"vendor":"Red Hat","product":"Red Hat Data Grid 8","collectionURL":"https://access.redhat.com/downloads/content/package-browser/","packageName":"keycloak-services","defaultStatus":"unaffected","cpes":["cpe:/a:redhat:jboss_data_grid:8"]},{"vendor":"Red Hat","product":"Red Hat JBoss Enterprise Application Platform Expansion Pack","collectionURL":"https://access.redhat.com/jbossnetwork/restricted/listSoftware.html","packageName":"keycloak-services","defaultStatus":"unaffected","cpes":["cpe:/a:redhat:jbosseapxp"]},{"vendor":"Red Hat","product":"Red Hat Single Sign-On 7","collectionURL":"https://access.redhat.com/downloads/content/package-browser/","packageName":"keycloak-services","defaultStatus":"unaffected","cpes":["cpe:/a:redhat:red_hat_single_sign_on:7"]}],"references":[{"url":"https://access.redhat.com/errata/RHSA-2026:50848","name":"RHSA-2026:50848","tags":["vendor-advisory","x_refsource_REDHAT"]},{"url":"https://access.redhat.com/errata/RHSA-2026:50849","name":"RHSA-2026:50849","tags":["vendor-advisory","x_refsource_REDHAT"]},{"url":"https://access.redhat.com/security/cve/CVE-2026-16100","tags":["vdb-entry","x_refsource_REDHAT"]},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2501730","name":"RHBZ#2501730","tags":["issue-tracking","x_refsource_REDHAT"]}],"datePublic":"2026-08-05T02:02:00.000Z","workarounds":[{"lang":"en","value":"Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability."}],"timeline":[{"lang":"en","time":"2026-07-14T17:46:38.000Z","value":"Reported to Red Hat."},{"lang":"en","time":"2026-08-05T02:02:00.000Z","value":"Made public."}],"credits":[{"lang":"en","value":"Red Hat would like to thank Paul Bottinelli (Trail of Bits) for reporting this issue."}],"providerMetadata":{"orgId":"53f830b8-0a3f-465b-8143-3b8a9948e749","shortName":"redhat","dateUpdated":"2026-08-05T18:45:38.602Z"},"x_generator":{"engine":"cvelib 1.8.0"}},"adp":[{"problemTypes":[{"descriptions":[{"type":"CWE","cweId":"CWE-770","lang":"en","description":"CWE-770 Allocation of Resources Without Limits or Throttling"}]}],"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-08-05T17:34:42.457705Z","id":"CVE-2026-16100","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"title":"CISA ADP Vulnrichment","providerMetadata":{"orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","shortName":"CISA-ADP","dateUpdated":"2026-08-05T17:38:57.112Z"}}]}}