{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "packageURL": "pkg:pypi/markdown",
          "product": "Markdown",
          "repo": "https://github.com/Python-Markdown/markdown",
          "vendor": "Python-Markdown",
          "versions": [
            {
              "lessThanOrEqual": "3.11.2",
              "status": "affected",
              "version": "3.0",
              "versionType": "custom"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:a:python-markdown2_project:python-markdown2:*:*:*:*:*:*:*:*",
                  "versionEndIncluding": "3.11.2",
                  "versionStartIncluding": "3.0",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "type": "finder",
          "value": "Anders Kaseorg"
        },
        {
          "lang": "en",
          "type": "finder",
          "value": "Muhammadyusuf Dilmurodov (agrresore)"
        }
      ],
      "datePublic": "2019-03-06T00:00:00.000Z",
      "descriptions": [
        {
          "lang": "en",
          "value": "Python-Markdown 3.0 through 3.11.2 contains an algorithmic complexity vulnerability in inline link parsing that allows remote attackers to exhaust CPU through unmatched brackets. Attackers can submit short Markdown containing repeated [ or ![ characters, forcing LinkInlineProcessor.getText() and getLink() into quadratic scans that keep workers busy for minutes."
        }
      ],
      "metrics": [
        {
          "cvssV4_0": {
            "attackComplexity": "LOW",
            "attackRequirements": "NONE",
            "attackVector": "NETWORK",
            "baseScore": 8.7,
            "baseSeverity": "HIGH",
            "privilegesRequired": "NONE",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "NONE",
            "subIntegrityImpact": "NONE",
            "userInteraction": "NONE",
            "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N",
            "version": "4.0",
            "vulnAvailabilityImpact": "HIGH",
            "vulnConfidentialityImpact": "NONE",
            "vulnIntegrityImpact": "NONE"
          },
          "format": "CVSS"
        },
        {
          "cvssV3_1": {
            "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"
          },
          "format": "CVSS"
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-407",
              "description": "Inefficient Algorithmic Complexity",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-10-29T13:08:49.597Z",
        "orgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
        "shortName": "VulnCheck"
      },
      "references": [
        {
          "name": "GitHub Issue #798",
          "tags": [
            "issue-tracking"
          ],
          "url": "https://github.com/Python-Markdown/markdown/issues/798"
        },
        {
          "tags": [
            "product"
          ],
          "url": "https://github.com/Python-Markdown/markdown"
        },
        {
          "name": "GitHub Issue #1654",
          "tags": [
            "issue-tracking"
          ],
          "url": "https://github.com/Python-Markdown/markdown/issues/1654"
        },
        {
          "tags": [
            "technical-description"
          ],
          "url": "https://github.com/Python-Markdown/markdown/blob/b41e0aaf1181f1a8cb200cf5a815aad7c0020d23/markdown/inlinepatterns.py#L1155-L1172"
        },
        {
          "name": "VulnCheck Advisory: Python-Markdown 3.0 through 3.11.2 Denial of Service via Link Bracket Parsing",
          "tags": [
            "third-party-advisory"
          ],
          "url": "https://www.vulncheck.com/advisories/python-markdown-3.0-through-3.11.2-denial-of-service-via-link-bracket-parsing"
        }
      ],
      "title": "Python-Markdown 3.0 through 3.11.2 Denial of Service via Link Bracket Parsing",
      "x_generator": {
        "engine": "vulncheck-endgame"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
    "assignerShortName": "VulnCheck",
    "cveId": "CVE-2019-25781",
    "datePublished": "2026-10-29T13:08:49.597Z",
    "dateReserved": "2026-10-29T11:51:49.648Z",
    "dateUpdated": "2026-10-29T13:08:49.597Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}