{"id":"CVE-2026-42581","summary":"Netty: HTTP/1.0 TE+CL Coexistence Bypasses Smuggling Sanitization","details":"Netty is an asynchronous, event-driven network application framework. Prior to 4.2.13.Final and 4.1.133.Final, HttpObjectDecoder strips a conflicting Content-Length header when a request carries both Transfer-Encoding: chunked and Content-Length, but only for HTTP/1.1 messages. The guard is absent for HTTP/1.0. An attacker that sends an HTTP/1.0 request with both headers causes Netty to decode the body as chunked while leaving Content-Length intact in the forwarded HttpMessage. Any downstream proxy or handler that trusts Content-Length over Transfer-Encoding will disagree on message boundaries, enabling request smuggling. This vulnerability is fixed in 4.2.13.Final and 4.1.133.Final.","aliases":["GHSA-xxqh-mfjm-7mv9"],"modified":"2026-05-20T04:03:09.619256725Z","published":"2026-05-13T17:54:44.492Z","related":["CGA-62c6-g27h-gjqm","openSUSE-SU-2026:10795-1"],"database_specific":{"cna_assigner":"GitHub_M","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/42xxx/CVE-2026-42581.json","cwe_ids":["CWE-444"]},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/42xxx/CVE-2026-42581.json"},{"type":"ADVISORY","url":"https://github.com/netty/netty/security/advisories/GHSA-xxqh-mfjm-7mv9"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-42581"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/netty/netty","events":[{"introduced":"5451fbb0effd8460f57013bb33aefeb953144ed9"},{"fixed":"fb13125f135ab53203513ff603872a3abe84d38d"}]}],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-42581.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N"}]}