{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "cpe": "cpe:2.3:a:fastapiexpert:python-multipart:*:*:*:*:*:python:*:*",
            "extracted_events": [
              {
                "introduced": "0"
              },
              {
                "fixed": "0.0.26"
              }
            ],
            "source": [
              "AFFECTED_FIELD",
              "CPE_RANGE",
              "REFERENCES"
            ]
          },
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "28f47859b4a40c2e11e02dc514b2e9743ceedd2e"
            }
          ],
          "repo": "https://github.com/kludex/python-multipart",
          "type": "GIT"
        }
      ]
    }
  ],
  "aliases": [
    "GHSA-mj87-hwqh-73pj"
  ],
  "database_specific": {
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
      "CWE-400",
      "CWE-834"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/40xxx/CVE-2026-40347.json"
  },
  "details": "Python-Multipart is a streaming multipart parser for Python. Versions prior to 0.0.26 have a denial of service vulnerability when parsing crafted `multipart/form-data` requests with large preamble or epilogue sections. Upgrade to version 0.0.26 or later, which skips ahead to the next boundary candidate when processing leading CR/LF data and immediately discards epilogue data after the closing boundary.",
  "id": "CVE-2026-40347",
  "modified": "2026-07-08T05:37:46.643089510Z",
  "published": "2026-04-17T23:56:50.777Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/Kludex/python-multipart/releases/tag/0.0.26"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/40xxx/CVE-2026-40347.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/Kludex/python-multipart/security/advisories/GHSA-mj87-hwqh-73pj"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-40347"
    }
  ],
  "schema_version": "1.7.5",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Python-Multipart affected by Denial of Service via large multipart preamble or epilogue data"
}