Security advisory

{
  "id": "bf9a6bbe2e91fe5ebf98a4b8ef06c1fa863a10d2bd7cadb1c5104b0069f002d7",
  "url": "https://osv.dev/vulnerability/CVE-2021-28833",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "CVE-2021-28833",
    "summary": "Increments Qiita::Markdown before 0.34.0 allows XSS via a crafted gist link, a different vulnerability than CVE-2021-28796.",
    "evidence": "osv:CVE-2021-28833",
    "products": [],
    "severity": "medium",
    "structured": {
      "id": "CVE-2021-28833",
      "aliases": [
        "CVE-2021-28833",
        "GHSA-9p29-94hp-8rvc"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/increments/qiita-markdown",
              "type": "GIT",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "fixed": "bd8b19975ee809562515ca6d7bdb85c3b0321c0c"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "cpe": "cpe:2.3:a:increments:qiita\\:\\:markdown:*:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "0"
                      },
                      {
                        "fixed": "0.34.0"
                      }
                    ],
                    "source": "CPE_RANGE"
                  }
                ]
              }
            }
          ],
          "versions": [
            "v0.33.0",
            "v0.32.0",
            "v0.31.0",
            "v0.30.0",
            "v0.29.0",
            "v0.28.0",
            "v0.27.0",
            "v0.26.0",
            "v0.25.0",
            "v0.24.0",
            "v0.23.0",
            "v0.22.0",
            "v0.21.0",
            "v0.20.1",
            "v0.20.0",
            "v0.19.1",
            "v0.19.0",
            "v0.18.0",
            "v0.17.0",
            "v0.16.1",
            "v0.16.0",
            "v0.15.0",
            "v0.14.0",
            "v0.13.0",
            "v0.12.0",
            "v0.11.5",
            "v0.11.4",
            "v0.11.3",
            "v0.11.2",
            "v0.11.1",
            "v0.11.0",
            "v0.10.0",
            "v0.9.0",
            "v0.8.1",
            "v0.8.0",
            "v0.7.1",
            "v0.7.0",
            "v0.6.0",
            "v0.5.0",
            "v0.4.2",
            "v0.4.1",
            "v0.4.0",
            "v0.3.0",
            "v0.2.2",
            "v0.2.1",
            "v0.2.0",
            "v0.1.9",
            "v0.1.8",
            "v0.1.7",
            "v0.1.6",
            "v0.1.5",
            "v0.1.4",
            "v0.1.3",
            "v0.1.2",
            "v0.1.1",
            "v0.1.0",
            "v0.0.9",
            "v0.0.8",
            "v0.0.7",
            "v0.0.6",
            "v0.0.5",
            "v0.0.4",
            "v0.0.3",
            "v0.0.2",
            "v0.0.1"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-28833.json"
          }
        }
      ],
      "modified": "2026-10-20T10:54:37.344139194Z",
      "provider": "osv",
      "references": [
        "https://github.com/increments/qiita-markdown/releases",
        "https://vuln.ryotak.me/advisories/50"
      ],
      "provider_metadata": {}
    },
    "related_cves": [
      {
        "value": "CVE-2021-28833",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 385767,
  "published_at": "2021-06-21T13:15:08.083+00:00"
}