{"api_version":"1","generated_at":"2026-07-29T20:34:10+00:00","cve":"CVE-2026-59898","urls":{"html":"https://cve.report/CVE-2026-59898","api":"https://cve.report/api/cve/CVE-2026-59898.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-59898","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-59898"},"summary":{"title":"Netty: WebSockets V07/V08 handshaker missing Connection/Upgrade validation","description":"Netty is an asynchronous, event-driven network application framework.  Prior to versions 4.1.136.Final and 4.2.16.Final, ab attacker can force WebSocket upgrade via the lax V07 (or V08) handshaker by sending `Sec-WebSocket-Version: 7` and omitting `Connection: Upgrade` / `Upgrade: websocket` headers, completing a protocol switch that a proxy would not recognize as an Upgrade request and enabling HTTP request smuggling / protocol-confusion attacks. 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Prior to versions 4.1.136.Final and 4.2.16.Final, ab attacker can force WebSocket upgrade via the lax V07 (or V08) handshaker by sending `Sec-WebSocket-Version: 7` and omitting `Connection: Upgrade` / `Upgrade: websocket` headers, completing a protocol switch that a proxy would not recognize as an Upgrade request and enabling HTTP request smuggling / protocol-confusion attacks. This issue has been fixed in versions 4.1.136.Final and 4.2.16.Final.","Type":"Description","Title":"Netty: WebSockets V07/V08 handshaker missing Connection/Upgrade "}]}}}