Security advisory

{
  "id": "9615fe3622819f0acf360de9bc6082db1a67300e9c03f12ea18988b5876a68f6",
  "url": "https://osv.dev/vulnerability/CVE-2018-1000874",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "CVE-2018-1000874",
    "summary": "PHP cebe markdown parser version 1.2.0 and earlier contains a Cross Site Scripting (XSS) vulnerability in all distributed parsers allowing a malicious crafted script to be executed that can result in the lose of user data and sensitive user information. This attack can be exploited by crafting a three backtick wrapped payload with a character in front: L: \"``````\". NOTE: This has been argued as a non-issue (see references) since it is not the parser's job to sanitize malicious code from a parsed document",
    "evidence": "osv:CVE-2018-1000874",
    "products": [],
    "severity": "medium",
    "structured": {
      "id": "CVE-2018-1000874",
      "aliases": [
        "CVE-2018-1000874"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/cebe/markdown",
              "type": "GIT",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "last_affected": "62efec06056b045c8c5e9c1126d9253ba27b9cb3"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "cpe": "cpe:2.3:a:cebe:markdown:*:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "0"
                      },
                      {
                        "last_affected": "1.2.0"
                      }
                    ],
                    "source": "CPE_RANGE"
                  }
                ]
              }
            }
          ],
          "versions": [
            "1.2.0",
            "1.1.2",
            "1.1.1",
            "1.1.0",
            "1.0.1",
            "1.0.0",
            "1.0.0-rc",
            "0.9.2",
            "0.9.1",
            "0.9.0"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2018-1000874.json"
          }
        }
      ],
      "modified": "2026-10-20T10:49:40.719103907Z",
      "provider": "osv",
      "references": [
        "https://github.com/cebe/markdown/issues/166",
        "https://github.com/cebe/markdown/issues/166#issuecomment-508230493"
      ],
      "provider_metadata": {}
    },
    "related_cves": [
      {
        "value": "CVE-2018-1000874",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 380676,
  "published_at": "2018-12-20T17:29:00.957+00:00"
}