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        "cveId": "CVE-2026-100663",
        "assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
        "state": "PUBLISHED",
        "assignerShortName": "VulnCheck",
        "dateReserved": "2026-09-26T02:33:59.039Z",
        "datePublished": "2026-09-26T13:23:29.751Z",
        "dateUpdated": "2026-09-28T18:48:51.788Z"
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                "dateUpdated": "2026-09-27T16:27:48.867Z"
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            "datePublic": "2026-09-10T00:00:00.000Z",
            "title": "Netty HTTP/1 CONNECT authority-form mistranslated to malformed HTTP/3",
            "descriptions": [
                {
                    "lang": "en",
                    "value": "Netty's HTTP/3 codec (io.netty:netty-codec-http3) from 4.2.2.Final through 4.2.17.Final does not special-case HTTP/1 CONNECT authority-form request-targets when converting HTTP/1 messages to HTTP/3 in HttpConversionUtil.toHttp3Headers. The authority-form target (e.g., \"CONNECT trusted.example:443\") is parsed as a URI, so its host is emitted as :scheme, :path is set to \"/\", and the HTTP/1 Host header is used as :authority; if no Host header is present the CONNECT target is dropped. In a Netty-based HTTP/1-to-HTTP/3 proxy or gateway, a remote client can send a CONNECT request whose Host header names a different authority than the request-target, producing a malformed HTTP/3 CONNECT whose tunnel :authority is attacker-controlled. This can bypass tunnel allow-lists, egress policy, backend selection, or audit controls that validate the HTTP/1 CONNECT request-target before forwarding over HTTP/3. The issue is fixed in 4.2.18.Final."
                }
            ],
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                {
                    "descriptions": [
                        {
                            "lang": "en",
                            "description": "Improper Input Validation",
                            "cweId": "CWE-20",
                            "type": "CWE"
                        }
                    ]
                }
            ],
            "affected": [
                {
                    "vendor": "netty",
                    "product": "netty",
                    "defaultStatus": "unaffected",
                    "packageURL": "pkg:maven/io.netty/netty-codec-http3",
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                            "version": "4.2.2.Final",
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                            "versionType": "custom",
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                        "attackVector": "NETWORK",
                        "attackComplexity": "LOW",
                        "attackRequirements": "NONE",
                        "privilegesRequired": "NONE",
                        "userInteraction": "NONE",
                        "vulnConfidentialityImpact": "NONE",
                        "vulnIntegrityImpact": "HIGH",
                        "vulnAvailabilityImpact": "NONE",
                        "subConfidentialityImpact": "NONE",
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                "title": "CISA ADP Vulnrichment",
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