CVE-2026-40561

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{"affected": [{"affectedData": [{"collectionURL": "https://cpan.org/modules", "defaultStatus": "unaffected", "packageName": "Starlet", "product": "Starlet", "programFiles": ["lib/Starlet/Server.pm"], "programRoutines": [{"name": "Starlet::Server::handle_connection"}], "repo": "https://github.com/kazuho/Starlet", "vendor": "KAZUHO", "versions": [{"lessThanOrEqual": "0.31", "status": "affected", "version": "0", "versionType": "custom"}]}], "source": "9b29abf9-4ab0-4765-b253-1875cd9b441e"}], "configurations": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:a:kazuho:starlet:*:*:*:*:*:perl:*:*", "matchCriteriaId": "D7E737B0-BC8D-4FDA-A6B2-E36FC466209A", "versionEndIncluding": "0.31", "vulnerable": true}], "negate": false, "operator": "OR"}]}], "cveTags": [], "descriptions": [{"lang": "en", "value": "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."}, {"lang": "es", "value": "Las versiones de Starlet hasta la 0.31 para Perl permiten el Contrabando de Solicitudes HTTP a trav\u00e9s de una Precedencia de Encabezado Inadecuada.\n\nStarlet prioriza incorrectamente \u2019Content-Length\u2019 sobre \u2019Transfer-Encoding: chunked\u2019 cuando ambos encabezados est\u00e1n presentes en una solicitud HTTP. Seg\u00fan la RFC 7230 3.3.3, Transfer-Encoding debe tener precedencia.\n\nUn atacante podr\u00eda explotar esto para contrabandear solicitudes HTTP maliciosas a trav\u00e9s de un proxy inverso de front-end."}], "id": "CVE-2026-40561", "lastModified": "2026-10-26T20:10:00.160", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 5.3, "baseSeverity": "MEDIUM", "confidentialityImpact": "NONE", "integrityImpact": "LOW", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N", "version": "3.1"}, "exploitabilityScore": 3.9, "impactScore": 1.4, "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-40561", "options": [{"exploitation": "none"}, {"automatable": "yes"}, {"technicalImpact": "partial"}], "role": "CISA Coordinator", "timestamp": "2026-05-04T13:54:42.679845Z", "version": "2.0.3"}}]}, "published": "2026-05-03T01:15:58.390", "references": [{"source": "9b29abf9-4ab0-4765-b253-1875cd9b441e", "tags": ["Third Party Advisory"], "url": "https://datatracker.ietf.org/doc/html/rfc7230#section-3.3.3"}, {"source": "9b29abf9-4ab0-4765-b253-1875cd9b441e", "tags": ["Patch"], "url": "https://github.com/kazuho/Starlet/commit/a7d5dfd1862aafa43e5eaca0fdb6acf4cc15b2d0.patch"}, {"source": "9b29abf9-4ab0-4765-b253-1875cd9b441e", "url": "https://metacpan.org/release/KAZUHO/Starlet-0.32/changes"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Mailing List", "Third Party Advisory"], "url": "http://www.openwall.com/lists/oss-security/2026/05/03/1"}], "sourceIdentifier": "9b29abf9-4ab0-4765-b253-1875cd9b441e", "vulnStatus": "Modified", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-444"}], "source": "9b29abf9-4ab0-4765-b253-1875cd9b441e", "type": "Secondary"}]}

{}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "generic", "value": "[0,0.31]"}}], "enrichment": {"confidence": 100.0, "confidence_source": "cna", "scores": [{"score": 100.0, "source": "cna"}]}, "original": {"product": "Starlet", "source": "cna", "vendor": "KAZUHO"}, "product": "starlet", "vendor": "kazuho"}], "created": "2026-05-03T02:30:05.816471+00:00", "updated": "2026-05-04T16:06:41.318918+00:00", "vendors": ["kazuho", "kazuho$PRODUCT$starlet"]}