CVE-2026-100663

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{"bugzilla": {"description": "io.netty/netty-codec-http3: netty-codec-http3: Security policy bypass via improper HTTP/1 to HTTP/3 CONNECT request translation", "id": "2541850", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2541850"}, "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 (netty-codec-http3). A remote attacker can bypass security policies and tunnel allowlists when Netty acts as an HTTP/1 to HTTP/3 proxy or gateway. Due to improper translation of HTTP/1 CONNECT requests, the component uses the attacker-controlled Host header to establish the HTTP/3 connection rather than the validated request target. By sending a request with conflicting destination headers, an attacker can route traffic to unauthorized backend services and circumvent egress filtering or audit controls."], "name": "CVE-2026-100663", "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": "2026-09-26T13:23:29Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-100663\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-100663\nhttps://github.com/netty/netty/security/advisories/GHSA-jgph-cgq3-c627\nhttps://www.vulncheck.com/advisories/netty-http-1-connect-authority-form-mistranslated-to-malformed-http-3"], "threat_severity": "Important"}

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