{"api_version":"1","generated_at":"2026-07-29T23:34:53+00:00","cve":"CVE-2026-59921","urls":{"html":"https://cve.report/CVE-2026-59921","api":"https://cve.report/api/cve/CVE-2026-59921.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-59921","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-59921"},"summary":{"title":"Netty: CRLF Injection via Multipart Filename in Netty HttpPostRequestEncoder","description":"Netty is an asynchronous, event-driven network application framework. Prior to versions 4.1.136.Final and 4.2.16.Final, HttpPostRequestEncoder constructs multipart HTTP request bodies by directly concatenating user-supplied filenames and field names into Content-Disposition MIME headers without validating or sanitizing CRLF characters (\\r\\n). Since MIME headers are delimited by CRLF, an attacker who controls the filename can inject arbitrary MIME headers into the multipart body part. 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