{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-18211","assignerOrgId":"53f830b8-0a3f-465b-8143-3b8a9948e749","state":"PUBLISHED","assignerShortName":"redhat","dateReserved":"2026-07-29T08:24:18.687Z","datePublished":"2026-07-31T07:08:24.767Z","dateUpdated":"2026-07-31T14:56:13.354Z"},"containers":{"cna":{"title":"Keycloak-services: keycloak-services: secure-client-uris policy bypass via localhost-prefixed domains","metrics":[{"other":{"content":{"value":"Moderate","namespace":"https://access.redhat.com/security/updates/classification/"},"type":"Red Hat severity rating"}},{"cvssV3_1":{"attackComplexity":"HIGH","attackVector":"NETWORK","availabilityImpact":"NONE","baseScore":4.2,"baseSeverity":"MEDIUM","confidentialityImpact":"LOW","integrityImpact":"LOW","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"REQUIRED","vectorString":"CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:N","version":"3.1"},"format":"CVSS"}],"descriptions":[{"lang":"en","value":"A flaw was found in the secure-client-uris client policy executor within Keycloak core services. This component is responsible for enforcing security requirements on client configurations, such as requiring encrypted connections for redirect URIs. Due to an improper check that only looks at the start of a web address rather than properly verifying the host, an attacker can bypass these security restrictions by using a specially crafted domain name. This could allow an attacker to intercept sensitive authentication codes over unencrypted connections."}],"affected":[{"vendor":"Red Hat","product":"Red Hat Build of Keycloak","collectionURL":"https://access.redhat.com/downloads/content/package-browser/","packageName":"keycloak-services","defaultStatus":"affected","cpes":["cpe:/a:redhat:build_keycloak:"]},{"vendor":"Red Hat","product":"Red Hat Build of Keycloak","collectionURL":"https://access.redhat.com/downloads/content/package-browser/","packageName":"rhbk-keycloak-rhel9/rhbk-keycloak-rhel9","defaultStatus":"affected","cpes":["cpe:/a:redhat:build_keycloak:"]},{"vendor":"Red Hat","product":"Red Hat Build of Keycloak","collectionURL":"https://access.redhat.com/downloads/content/package-browser/","packageName":"rhbk-openshift-rhel9/rhbk-openshift-rhel9","defaultStatus":"affected","cpes":["cpe:/a:redhat:build_keycloak:"]},{"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/security/cve/CVE-2026-18211","tags":["vdb-entry","x_refsource_REDHAT"]},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2508306","name":"RHBZ#2508306","tags":["issue-tracking","x_refsource_REDHAT"]}],"datePublic":"2026-07-28T12:55:48.000Z","problemTypes":[{"descriptions":[{"cweId":"CWE-20","description":"Improper Input Validation","lang":"en","type":"CWE"}]}],"x_redhatCweChain":"CWE-20: Improper Input Validation","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":"2026-07-28T12:55:48.000Z","value":"Reported to Red Hat."},{"lang":"en","time":"2026-07-28T12:55:48.000Z","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":"2026-07-31T07:08:24.767Z"},"x_generator":{"engine":"cvelib 1.8.0"}},"adp":[{"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-07-31T14:56:05.376191Z","id":"CVE-2026-18211","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":"2026-07-31T14:56:13.354Z"}}]}}