FKIE_CVE-2020-28493

Vulnerability from fkie_nvd - Published: 2021-02-01 20:15 - Updated: 2026-06-17 03:10
Severity
5.3 (Medium) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
5.3 (Medium) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
Summary
This affects the package jinja2 from 0.0.0 and before 2.11.3. The ReDoS vulnerability is mainly due to the `_punctuation_re regex` operator and its use of multiple wildcards. The last wildcard is the most exploitable as it searches for trailing punctuation. This issue can be mitigated by Markdown to format user content instead of the urlize filter, or by implementing request timeouts and limiting process memory.
References
report@snyk.iohttps://github.com/pallets/jinja/blob/ab81fd9c277900c85da0c322a2ff9d68a235b2e6/src/jinja2/utils.py%23L20Broken Link
report@snyk.iohttps://github.com/pallets/jinja/pull/1343Patch, Third Party Advisory
report@snyk.iohttps://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/PVAKCOO7VBVUBM3Q6CBBTPBFNP5NDXF4/
report@snyk.iohttps://security.gentoo.org/glsa/202107-19Third Party Advisory
report@snyk.iohttps://snyk.io/vuln/SNYK-PYTHON-JINJA2-1012994Exploit, Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://github.com/pallets/jinja/blob/ab81fd9c277900c85da0c322a2ff9d68a235b2e6/src/jinja2/utils.py%23L20Broken Link
af854a3a-2127-422b-91ae-364da2661108https://github.com/pallets/jinja/pull/1343Patch, Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/PVAKCOO7VBVUBM3Q6CBBTPBFNP5NDXF4/
af854a3a-2127-422b-91ae-364da2661108https://security.gentoo.org/glsa/202107-19Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://snyk.io/vuln/SNYK-PYTHON-JINJA2-1012994Exploit, Third Party Advisory
Impacted products
Vendor Product Version
palletsprojects jinja *
fedoraproject fedora 33
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "jinja2",
          "vendor": "n/a",
          "versions": [
            {
              "lessThan": "unspecified",
              "status": "affected",
              "version": "0.0.0",
              "versionType": "custom"
            },
            {
              "lessThan": "2.11.3",
              "status": "affected",
              "version": "unspecified",
              "versionType": "custom"
            }
          ]
        }
      ],
      "source": "report@snyk.io"
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:a:palletsprojects:jinja:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "B4C4464D-515B-4608-96F0-D7282C5AA582",
              "versionEndExcluding": "2.11.3",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    },
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:*",
              "matchCriteriaId": "E460AA51-FCDA-46B9-AE97-E6676AA5E194",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "This affects the package jinja2 from 0.0.0 and before 2.11.3. The ReDoS vulnerability is mainly due to the `_punctuation_re regex` operator and its use of multiple wildcards. The last wildcard is the most exploitable as it searches for trailing punctuation. This issue can be mitigated by Markdown to format user content instead of the urlize filter, or by implementing request timeouts and limiting process memory."
    },
    {
      "lang": "es",
      "value": "Esto afecta al paquete jinja2 desde versiones 0.0.0 y anteriores a 2.11.3. La vulnerabilidad ReDoS se debe principalmente al operador `_punctuation_re regex` y su uso de m\u00faltiples comodines. El \u00faltimo comod\u00edn es el m\u00e1s explotable, ya que busca la puntuaci\u00f3n final. Este problema puede ser mitigado con Markdown para formatear el contenido del usuario en lugar del filtro urlize, o implementando tiempos de espera de las peticiones y limitando la memoria del proceso"
    }
  ],
  "id": "CVE-2020-28493",
  "lastModified": "2026-06-17T03:10:32.070",
  "metrics": {
    "cvssMetricV2": [
      {
        "acInsufInfo": false,
        "baseSeverity": "MEDIUM",
        "cvssData": {
          "accessComplexity": "LOW",
          "accessVector": "NETWORK",
          "authentication": "NONE",
          "availabilityImpact": "PARTIAL",
          "baseScore": 5.0,
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "vectorString": "AV:N/AC:L/Au:N/C:N/I:N/A:P",
          "version": "2.0"
        },
        "exploitabilityScore": 10.0,
        "impactScore": 2.9,
        "obtainAllPrivilege": false,
        "obtainOtherPrivilege": false,
        "obtainUserPrivilege": false,
        "source": "nvd@nist.gov",
        "type": "Primary",
        "userInteractionRequired": false
      }
    ],
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "LOW",
          "baseScore": 5.3,
          "baseSeverity": "MEDIUM",
          "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:L",
          "version": "3.1"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 1.4,
        "source": "report@snyk.io",
        "type": "Secondary"
      },
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "LOW",
          "baseScore": 5.3,
          "baseSeverity": "MEDIUM",
          "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:L",
          "version": "3.1"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 1.4,
        "source": "nvd@nist.gov",
        "type": "Primary"
      }
    ]
  },
  "published": "2021-02-01T20:15:12.517",
  "references": [
    {
      "source": "report@snyk.io",
      "tags": [
        "Broken Link"
      ],
      "url": "https://github.com/pallets/jinja/blob/ab81fd9c277900c85da0c322a2ff9d68a235b2e6/src/jinja2/utils.py%23L20"
    },
    {
      "source": "report@snyk.io",
      "tags": [
        "Patch",
        "Third Party Advisory"
      ],
      "url": "https://github.com/pallets/jinja/pull/1343"
    },
    {
      "source": "report@snyk.io",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/PVAKCOO7VBVUBM3Q6CBBTPBFNP5NDXF4/"
    },
    {
      "source": "report@snyk.io",
      "tags": [
        "Third Party Advisory"
      ],
      "url": "https://security.gentoo.org/glsa/202107-19"
    },
    {
      "source": "report@snyk.io",
      "tags": [
        "Exploit",
        "Third Party Advisory"
      ],
      "url": "https://snyk.io/vuln/SNYK-PYTHON-JINJA2-1012994"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Broken Link"
      ],
      "url": "https://github.com/pallets/jinja/blob/ab81fd9c277900c85da0c322a2ff9d68a235b2e6/src/jinja2/utils.py%23L20"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Patch",
        "Third Party Advisory"
      ],
      "url": "https://github.com/pallets/jinja/pull/1343"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/PVAKCOO7VBVUBM3Q6CBBTPBFNP5NDXF4/"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Third Party Advisory"
      ],
      "url": "https://security.gentoo.org/glsa/202107-19"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Exploit",
        "Third Party Advisory"
      ],
      "url": "https://snyk.io/vuln/SNYK-PYTHON-JINJA2-1012994"
    }
  ],
  "sourceIdentifier": "report@snyk.io",
  "vulnStatus": "Modified",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-400"
        }
      ],
      "source": "nvd@nist.gov",
      "type": "Primary"
    }
  ]
}



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