CVE-2026-100664

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{"bugzilla": {"description": "io.netty/netty-codec-http3: Netty: Security bypass via HTTP Host header authority confusion", "id": "2541881", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2541881"}, "csaw": false, "cvss3": {"cvss3_base_score": "7.5", "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N", "status": "draft"}, "cwe": "CWE-444", "details": ["A flaw was found in Netty's HTTP/3 codec. When converting HTTP/1 requests to HTTP/3, the codec improperly prioritizes the Host header over the request-target authority. A remote, unauthenticated attacker can exploit this authority confusion by sending a request containing conflicting destination details through an intermediary proxy or gateway. This flaw can lead to security bypasses, enabling attackers to circumvent access controls, route traffic to unintended backend systems, or poison web caches."], "name": "CVE-2026-100664", "package_state": [{"cpe": "cpe:/a:redhat:openshift_ai", "fix_state": "Affected", "package_name": "rhoai/odh-th-torch-cpu-py312-rhel9", "product_name": "Red Hat OpenShift AI (RHOAI)"}, {"cpe": "cpe:/a:redhat:openshift_ai", "fix_state": "Affected", "package_name": "rhoai/odh-th-torch-cuda-py312-rhel9", "product_name": "Red Hat OpenShift AI (RHOAI)"}, {"cpe": "cpe:/a:redhat:openshift_devspaces:3", "fix_state": "Affected", "package_name": "devspaces/openvsx-rhel9", "product_name": "Red Hat OpenShift Dev Spaces"}, {"cpe": "cpe:/a:redhat:openshift_devspaces:3", "fix_state": "Affected", "package_name": "devspaces/pluginregistry-rhel9", "product_name": "Red Hat OpenShift Dev Spaces"}], "public_date": "2026-09-26T13:23:30Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-100664\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-100664\nhttps://github.com/netty/netty/security/advisories/GHSA-hfr2-x62w-v49h\nhttps://www.vulncheck.com/advisories/netty-4.2.2-through-4.2.15-http-1-host-header-authority-confusion"], "threat_severity": "Important"}

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