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FKIE_CVE-2020-26256

Vulnerability from fkie_nvd - Published: 2020-12-08 22:15 - Updated: 2026-06-17 03:07
Severity
5.7 (Medium) - CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:N/A:H
6.5 (Medium) - CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Summary
Fast-csv is an npm package for parsing and formatting CSVs or any other delimited value file in node. In fast-cvs before version 4.3.6 there is a possible ReDoS vulnerability (Regular Expression Denial of Service) when using ignoreEmpty option when parsing. This has been patched in `v4.3.6` You will only be affected by this if you use the `ignoreEmpty` parsing option. If you do use this option it is recommended that you upgrade to the latest version `v4.3.6` This vulnerability was found using a CodeQL query which identified `EMPTY_ROW_REGEXP` regular expression as vulnerable.
References
security-advisories@github.comhttps://github.com/C2FO/fast-csv/commit/4bbd39f26a8cd7382151ab4f5fb102234b2f829ePatch, Third Party Advisory
security-advisories@github.comhttps://github.com/C2FO/fast-csv/issues/540Third Party Advisory
security-advisories@github.comhttps://github.com/C2FO/fast-csv/security/advisories/GHSA-8cv5-p934-3hwpThird Party Advisory
security-advisories@github.comhttps://lgtm.com/query/8609731774537641779/Exploit, Third Party Advisory
security-advisories@github.comhttps://www.npmjs.com/package/%40fast-csv/parse
security-advisories@github.comhttps://www.npmjs.com/package/fast-csvProduct, Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://github.com/C2FO/fast-csv/commit/4bbd39f26a8cd7382151ab4f5fb102234b2f829ePatch, Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://github.com/C2FO/fast-csv/issues/540Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://github.com/C2FO/fast-csv/security/advisories/GHSA-8cv5-p934-3hwpThird Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://lgtm.com/query/8609731774537641779/Exploit, Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://www.npmjs.com/package/%40fast-csv/parse
af854a3a-2127-422b-91ae-364da2661108https://www.npmjs.com/package/fast-csvProduct, Third Party Advisory
Impacted products
Vendor Product Version
c2fo fast-csv *
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "fast-csv",
          "vendor": "C2FO",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 4.3.6"
            }
          ]
        }
      ],
      "source": "security-advisories@github.com"
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:a:c2fo:fast-csv:*:*:*:*:*:node.js:*:*",
              "matchCriteriaId": "38FF4853-5265-411D-91CC-D0137CBE216E",
              "versionEndExcluding": "4.3.6",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Fast-csv is an npm package for parsing and formatting CSVs or any other delimited value file in node. In fast-cvs before version 4.3.6 there is a possible ReDoS vulnerability (Regular Expression Denial of Service) when using ignoreEmpty option when parsing. This has been patched in `v4.3.6` You will only be affected by this if you use the `ignoreEmpty` parsing option. If you do use this option it is recommended that you upgrade to the latest version `v4.3.6` This vulnerability was found using a CodeQL query which identified `EMPTY_ROW_REGEXP` regular expression as vulnerable."
    },
    {
      "lang": "es",
      "value": "Fast-csv es un paquete npm para analizar y formatear CSV o cualquier otro archivo de valor delimitado en node.\u0026#xa0;En fast-cvs anterior a versi\u00f3n 4.3.6, se presenta una posible vulnerabilidad ReDoS (Denegaci\u00f3n de servicio de expresi\u00f3n regular) cuando se usa la opci\u00f3n ignoreEmpty al analizar.\u0026#xa0;Esto ha sido parcheado en versi\u00f3n \"v4.3.6\" Solo se ver\u00e1 afectado por esto si utiliza la opci\u00f3n de an\u00e1lisis \"ignoreEmpty\".\u0026#xa0;Si usa esta opci\u00f3n, se recomienda que actualice a la \u00faltima versi\u00f3n \"v4.3.6\". Esta vulnerabilidad se encontr\u00f3 usando una consulta CodeQL que identific\u00f3 la expresi\u00f3n regular \"EMPTY_ROW_REGEXP\" como vulnerable"
    }
  ],
  "id": "CVE-2020-26256",
  "lastModified": "2026-06-17T03:07:56.073",
  "metrics": {
    "cvssMetricV2": [
      {
        "acInsufInfo": false,
        "baseSeverity": "LOW",
        "cvssData": {
          "accessComplexity": "MEDIUM",
          "accessVector": "NETWORK",
          "authentication": "SINGLE",
          "availabilityImpact": "PARTIAL",
          "baseScore": 3.5,
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "vectorString": "AV:N/AC:M/Au:S/C:N/I:N/A:P",
          "version": "2.0"
        },
        "exploitabilityScore": 6.8,
        "impactScore": 2.9,
        "obtainAllPrivilege": false,
        "obtainOtherPrivilege": false,
        "obtainUserPrivilege": false,
        "source": "nvd@nist.gov",
        "type": "Primary",
        "userInteractionRequired": false
      }
    ],
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "HIGH",
          "baseScore": 5.7,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "privilegesRequired": "LOW",
          "scope": "UNCHANGED",
          "userInteraction": "REQUIRED",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:N/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 2.1,
        "impactScore": 3.6,
        "source": "security-advisories@github.com",
        "type": "Secondary"
      },
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "HIGH",
          "baseScore": 6.5,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "privilegesRequired": "LOW",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 2.8,
        "impactScore": 3.6,
        "source": "nvd@nist.gov",
        "type": "Primary"
      }
    ]
  },
  "published": "2020-12-08T22:15:17.540",
  "references": [
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      "source": "security-advisories@github.com",
      "tags": [
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        "Third Party Advisory"
      ],
      "url": "https://github.com/C2FO/fast-csv/commit/4bbd39f26a8cd7382151ab4f5fb102234b2f829e"
    },
    {
      "source": "security-advisories@github.com",
      "tags": [
        "Third Party Advisory"
      ],
      "url": "https://github.com/C2FO/fast-csv/issues/540"
    },
    {
      "source": "security-advisories@github.com",
      "tags": [
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      ],
      "url": "https://github.com/C2FO/fast-csv/security/advisories/GHSA-8cv5-p934-3hwp"
    },
    {
      "source": "security-advisories@github.com",
      "tags": [
        "Exploit",
        "Third Party Advisory"
      ],
      "url": "https://lgtm.com/query/8609731774537641779/"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://www.npmjs.com/package/%40fast-csv/parse"
    },
    {
      "source": "security-advisories@github.com",
      "tags": [
        "Product",
        "Third Party Advisory"
      ],
      "url": "https://www.npmjs.com/package/fast-csv"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Patch",
        "Third Party Advisory"
      ],
      "url": "https://github.com/C2FO/fast-csv/commit/4bbd39f26a8cd7382151ab4f5fb102234b2f829e"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
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      "url": "https://github.com/C2FO/fast-csv/issues/540"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
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      ],
      "url": "https://github.com/C2FO/fast-csv/security/advisories/GHSA-8cv5-p934-3hwp"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
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      ],
      "url": "https://lgtm.com/query/8609731774537641779/"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "url": "https://www.npmjs.com/package/%40fast-csv/parse"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
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      ],
      "url": "https://www.npmjs.com/package/fast-csv"
    }
  ],
  "sourceIdentifier": "security-advisories@github.com",
  "vulnStatus": "Modified",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-400"
        }
      ],
      "source": "security-advisories@github.com",
      "type": "Secondary"
    },
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-400"
        }
      ],
      "source": "nvd@nist.gov",
      "type": "Primary"
    }
  ]
}



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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
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