{"cve":"CVE-2025-58056","nvd":{"published":"2025-09-03T21:15:33.070","modified":"2026-10-19T17:10:00.173","status":"Analyzed","description":"Netty is an asynchronous event-driven network application framework for development of maintainable high performance protocol servers and clients. In versions 4.1.124.Final, and 4.2.0.Alpha3 through 4.2.4.Final, Netty incorrectly accepts standalone newline characters (LF) as a chunk-size line terminator, regardless of a preceding carriage return (CR), instead of requiring CRLF per HTTP/1.1 standards. When combined with reverse proxies that parse LF differently (treating it as part of the chunk extension), attackers can craft requests that the proxy sees as one request but Netty processes as two, enabling request smuggling attacks. This is fixed in versions 4.1.125.Final and 4.2.5.Final.","cvss_v4":{"vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:P","score":2.9},"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N","score":7.5},"cwes":["CWE-444"],"references":["https://datatracker.ietf.org/doc/html/rfc9112#name-chunked-transfer-coding","https://github.com/JLLeitschuh/unCVEed/issues/1","https://github.com/netty/netty/commit/edb55fd8e0a3bcbd85881e423464f585183d1284","https://github.com/netty/netty/issues/15522","https://github.com/netty/netty/pull/15611"],"products":["netty:netty"],"source":"nvd","synced_at":"2026-10-19T22:08:41.295252406+00:00"},"epss":{"cve":"CVE-2025-58056","score":0.0071,"percentile":0.53255,"date":"2026-10-25"},"kev":null,"osv":[{"id":"GHSA-fghv-69vj-qj49","url":"https://osv.dev/vulnerability/GHSA-fghv-69vj-qj49","summary":"Netty vulnerable to request smuggling due to incorrect parsing of chunk extensions","modified":"2026-09-10T03:50:28.333050757Z","packages":[{"ecosystem":"Maven","name":"io.netty:netty-codec-http","purl":"pkg:maven/io.netty/netty-codec-http","ranges":["<4.1.125.Final"],"fixed":["4.1.125.Final"]},{"ecosystem":"Maven","name":"io.netty:netty-codec-http","purl":"pkg:maven/io.netty/netty-codec-http","ranges":[">=4.2.0.Alpha1 <4.2.5.Final"],"fixed":["4.2.5.Final"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}