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GHSA-G3RQ-G295-4J3M

Vulnerability from github – Published: 2021-03-19 21:28 – Updated: 2024-09-24 20:40
VLAI
Summary
Regular Expression Denial of Service (ReDoS) in Jinja2
Details

This affects the package jinja2 from 0.0.0 and before 2.11.3. The ReDOS vulnerability of the regex is mainly due to the sub-pattern [a-zA-Z0-9.-]+.[a-zA-Z0-9.-]+ 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.

Severity
5.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
6.9 (Medium)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
Show details on source website
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{
  "affected": [
    {
      "package": {
        "ecosystem": "PyPI",
        "name": "Jinja2"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2.11.3"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2020-28493"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-400"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2021-03-13T01:08:09Z",
    "nvd_published_at": "2021-02-01T20:15:00Z",
    "severity": "MODERATE"
  },
  "details": "This affects the package jinja2 from 0.0.0 and before 2.11.3. The ReDOS vulnerability of the regex is mainly due to the sub-pattern [a-zA-Z0-9._-]+.[a-zA-Z0-9._-]+ 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.",
  "id": "GHSA-g3rq-g295-4j3m",
  "modified": "2024-09-24T20:40:19Z",
  "published": "2021-03-19T21:28:05Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2020-28493"
    },
    {
      "type": "WEB",
      "url": "https://github.com/pallets/jinja/pull/1343"
    },
    {
      "type": "WEB",
      "url": "https://github.com/pallets/jinja/commit/15ef8f09b659f9100610583938005a7a10472d4d"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/advisories/GHSA-g3rq-g295-4j3m"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/pallets/jinja"
    },
    {
      "type": "WEB",
      "url": "https://github.com/pallets/jinja/blob/ab81fd9c277900c85da0c322a2ff9d68a235b2e6/src/jinja2/utils.py%23L20"
    },
    {
      "type": "WEB",
      "url": "https://github.com/pypa/advisory-database/tree/main/vulns/jinja2/PYSEC-2021-66.yaml"
    },
    {
      "type": "WEB",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/PVAKCOO7VBVUBM3Q6CBBTPBFNP5NDXF4"
    },
    {
      "type": "WEB",
      "url": "https://security.gentoo.org/glsa/202107-19"
    },
    {
      "type": "WEB",
      "url": "https://snyk.io/vuln/SNYK-PYTHON-JINJA2-1012994"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "Regular Expression Denial of Service (ReDoS) in Jinja2"
}



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