FKIE_CVE-2026-28356

Vulnerability from fkie_nvd - Published: 2026-03-12 17:16 - Updated: 2026-03-12 21:07
Severity ?
7.5 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Summary
multipart is a fast multipart/form-data parser for python. Prior to 1.2.2, 1.3.1 and 1.4.0-dev, the parse_options_header() function in multipart.py uses a regular expression with an ambiguous alternation, which can cause exponential backtracking (ReDoS) when parsing maliciously crafted HTTP or multipart segment headers. This can be abused for denial of service (DoS) attacks against web applications using this library to parse request headers or multipart/form-data streams. The issue is fixed in 1.2.2, 1.3.1 and 1.4.0-dev.
References
security-advisories@github.comhttps://github.com/defnull/multipart/security/advisories/GHSA-p2m9-wcp5-6qw3
Impacted products
Vendor Product Version
To clipboard 

{
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "multipart is a fast multipart/form-data parser for python. Prior to 1.2.2, 1.3.1 and 1.4.0-dev, the parse_options_header() function in multipart.py uses a regular expression with an ambiguous alternation, which can cause exponential backtracking (ReDoS) when parsing maliciously crafted HTTP or multipart segment headers. This can be abused for denial of service (DoS) attacks against web applications using this library to parse request headers or multipart/form-data streams. The issue is fixed in 1.2.2, 1.3.1 and 1.4.0-dev."
    },
    {
      "lang": "es",
      "value": "multipart es un r\u00e1pido analizador de multipart/form-data para Python. Antes de 1.2.2, 1.3.1 y 1.4.0-dev, la funci\u00f3n parse_options_header() en multipart.py utiliza una expresi\u00f3n regular con una alternancia ambigua, lo que puede causar retroceso exponencial (ReDoS) al analizar encabezados HTTP o de segmento multipart maliciosamente elaborados. Esto puede ser abusado para ataques de denegaci\u00f3n de servicio (DoS) contra aplicaciones web que utilizan esta biblioteca para analizar encabezados de solicitud o flujos de multipart/form-data. El problema est\u00e1 solucionado en 1.2.2, 1.3.1 y 1.4.0-dev."
    }
  ],
  "id": "CVE-2026-28356",
  "lastModified": "2026-03-12T21:07:53.427",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "HIGH",
          "baseScore": 7.5,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 3.6,
        "source": "security-advisories@github.com",
        "type": "Secondary"
      }
    ]
  },
  "published": "2026-03-12T17:16:50.080",
  "references": [
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/defnull/multipart/security/advisories/GHSA-p2m9-wcp5-6qw3"
    }
  ],
  "sourceIdentifier": "security-advisories@github.com",
  "vulnStatus": "Awaiting Analysis",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-1333"
        }
      ],
      "source": "security-advisories@github.com",
      "type": "Primary"
    }
  ]
}


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