{"cve":"CVE-2026-40562","nvd":{"published":"2026-05-06T13:16:09.110","modified":"2026-10-26T19:10:00.163","status":"Analyzed","description":"Gazelle versions through 0.49 for Perl allows HTTP Request Smuggling via Improper Header Precedence.\n\nGazelle incorrectly prioritizes \"Content-Length\" over \"Transfer-Encoding: chunked\" when both headers are present in an HTTP request. Per RFC 7230 3.3.3, Transfer-Encoding must take precedence.\n\nAn attacker could exploit this to smuggle malicious HTTP requests via a front-end reverse proxy.","cvss_v4":null,"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/rfc7230#section-3.3.3","https://metacpan.org/release/KAZEBURO/Gazelle-0.50/changes","https://security.metacpan.org/patches/G/Gazelle/0.49/CVE-2026-40562-r1.patch","http://www.openwall.com/lists/oss-security/2026/05/06/7"],"products":["kazeburo:gazelle"],"source":"nvd","synced_at":"2026-10-26T19:31:02.781428341+00:00"},"epss":{"cve":"CVE-2026-40562","score":0.00319,"percentile":0.24653,"date":"2026-10-26"},"kev":null,"osv":[],"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."]}