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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."}],"impacts":[{"capecId":"CAPEC-33","descriptions":[{"lang":"en","value":"CAPEC-33 HTTP Request Smuggling"}]}],"problemTypes":[{"descriptions":[{"cweId":"CWE-444","description":"CWE-444 Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')","lang":"en","type":"CWE"}]}],"providerMetadata":{"dateUpdated":"2026-05-03T00:57:31.519Z","orgId":"9b29abf9-4ab0-4765-b253-1875cd9b441e","shortName":"CPANSec"},"references":[{"url":"https://datatracker.ietf.org/doc/html/rfc7230#section-3.3.3"},{"tags":["patch"],"url":"https://github.com/kazuho/Starlet/commit/a7d5dfd1862aafa43e5eaca0fdb6acf4cc15b2d0.patch"}],"source":{"discovery":"UNKNOWN"},"timeline":[{"lang":"en","time":"2026-04-12T00:00:00.000Z","value":"Issue identified"},{"lang":"en","time":"2026-04-28T00:00:00.000Z","value":"Maintainer notified"},{"lang":"en","time":"2026-05-02T00:00:00.000Z","value":"Determined that the issue was already public on GitHub"}],"title":"Starlet versions through 0.31 for Perl allows HTTP Request Smuggling via Improper Header Precedence","workarounds":[{"lang":"en","value":"Migrate to Starman 0.4018 or later which has fixed this issue or apply the patch."}],"x_generator":{"engine":"cpansec-cna-tool 0.1"}}},"cveMetadata":{"assignerOrgId":"9b29abf9-4ab0-4765-b253-1875cd9b441e","assignerShortName":"CPANSec","cveId":"CVE-2026-40561","datePublished":"2026-05-03T00:57:31.519Z","dateReserved":"2026-04-14T11:35:53.644Z","dateUpdated":"2026-05-03T03:04:55.098Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-05-03 01:15:58","lastModifiedDate":"2026-05-03 05:15:58","problem_types":["CWE-444","CWE-444 CWE-444 Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')"],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"40561","Ordinal":"1","Title":"Starlet versions through 0.31 for Perl allows HTTP Request Smugg","CVE":"CVE-2026-40561","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"40561","Ordinal":"1","NoteData":"Starlet versions through 0.31 for Perl allows HTTP Request Smuggling via Improper Header Precedence.\n\nStarlet 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.","Type":"Description","Title":"Starlet versions through 0.31 for Perl allows HTTP Request Smugg"}]}}}