{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-53538", "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "state": "PUBLISHED", "assignerShortName": "GitHub_M", "dateReserved": "2026-06-09T18:13:07.263Z", "datePublished": "2026-06-22T16:56:32.628Z", "dateUpdated": "2026-06-22T16:56:32.628Z"}, "containers": {"cna": {"title": "Python-Multipart: Semicolon treated as querystring field separator enables parameter smuggling", "problemTypes": [{"descriptions": [{"cweId": "CWE-436", "lang": "en", "description": "CWE-436: Interpretation Conflict", "type": "CWE"}]}, {"descriptions": [{"cweId": "CWE-444", "lang": "en", "description": "CWE-444: Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')", "type": "CWE"}]}], "metrics": [{"cvssV3_1": {"attackComplexity": "HIGH", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 3.7, "baseSeverity": "LOW", "confidentialityImpact": "NONE", "integrityImpact": "LOW", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N", "version": "3.1"}}], "references": [{"name": "https://github.com/Kludex/python-multipart/security/advisories/GHSA-6jv3-5f52-599m", "tags": ["x_refsource_CONFIRM"], "url": "https://github.com/Kludex/python-multipart/security/advisories/GHSA-6jv3-5f52-599m"}], "affected": [{"vendor": "Kludex", "product": "python-multipart", "versions": [{"version": "< 0.0.30", "status": "affected"}]}], "providerMetadata": {"orgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "shortName": "GitHub_M", "dateUpdated": "2026-06-22T16:56:32.628Z"}, "descriptions": [{"lang": "en", "value": "Python-Multipart is a streaming multipart parser for Python. Prior to 0.0.30, QuerystringParser treated ; as a field separator in application/x-www-form-urlencoded bodies, in addition to &. The WHATWG URL standard, modern browsers, and Python's urllib.parse (since the CVE-2021-23336 fix) treat only & as a separator. This creates a parser differential: the same bytes are tokenized into different fields than a WHATWG compliant intermediary would produce, allowing an attacker to smuggle extra form fields past an upstream body inspecting component. This vulnerability is fixed in 0.0.30."}], "source": {"advisory": "GHSA-6jv3-5f52-599m", "discovery": "UNKNOWN"}}}}

{}

{}

{}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[0,0.0.30)"}}], "enrichment": {"confidence": 100.0, "confidence_source": "matching", "scores": [{"score": 100.0, "source": "matching"}]}, "original": {"product": "python-multipart", "source": "cna", "vendor": "Kludex"}, "product": "python-multipart", "vendor": "kludex"}], "created": "2026-06-22T18:30:15.398447+00:00", "updated": "2026-06-22T20:00:06.000911+00:00", "vendors": ["kludex", "kludex$PRODUCT$python-multipart"]}