Security advisory

{
  "id": "0fc2d5708137eb5dbb696b80e592251cf6c29c11b02cc40b6b28cb7328f25bd5",
  "url": "https://osv.dev/vulnerability/CVE-2021-3866",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "CVE-2021-3866",
    "summary": "Cross-site Scripting (XSS) - Stored in GitHub repository zulip/zulip more than and including 44f935695d452cc3fb16845a0c6af710438b153d and prior to 3eb2791c3e9695f7d37ffe84e0c2184fae665cb6.",
    "evidence": "osv:CVE-2021-3866",
    "products": [],
    "severity": "medium",
    "structured": {
      "id": "CVE-2021-3866",
      "aliases": [
        "CVE-2021-3866"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/zulip/zulip",
              "type": "GIT",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "last_affected": "ae000bfdbaf428cb1f7164bab0668111e14d2304"
                },
                {
                  "fixed": "3eb2791c3e9695f7d37ffe84e0c2184fae665cb6"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "cpe": "cpe:2.3:a:zulip:zulip:*:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "0"
                      },
                      {
                        "last_affected": "4.8"
                      }
                    ],
                    "source": "CPE_RANGE"
                  },
                  {
                    "range": [
                      {
                        "fixed": "3eb2791c3e9695f7d37ffe84e0c2184fae665cb6"
                      }
                    ],
                    "source": "REFERENCES_COMMIT"
                  }
                ]
              }
            }
          ],
          "versions": [
            "4.8",
            "4.7",
            "4.6",
            "4.5",
            "4.4",
            "shared-0.0.6",
            "4.3",
            "4.2",
            "4.1",
            "4.0",
            "5.0-dev",
            "shared-0.0.5",
            "shared-0.0.4",
            "shared-0.0.3",
            "4.0-dev",
            "3.0",
            "3.0-rc2",
            "3.0-rc1",
            "3.0-dev",
            "2.2-dev",
            "2.1.0",
            "2.1.0-rc1",
            "shared-0.0.2",
            "shared-0.0.1",
            "2.0.0",
            "2.1-dev",
            "2.0.0-rc1",
            "1.9.0",
            "1.9.0-rc3",
            "1.9.0-rc2",
            "1.8.0",
            "1.8.0-rc1",
            "1.7.0",
            "1.6.0",
            "1.5.0",
            "1.4.0",
            "1.3.13",
            "1.3.11",
            "1.3.10",
            "1.3.9",
            "1.3.8",
            "1.3.7",
            "1.3.6",
            "1.3.5",
            "1.3.4",
            "1.3.3",
            "1.3.2",
            "1.3.1",
            "1.3.0",
            "enterprise-1.2.0",
            "enterprise-1.1.5"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-3866.json"
          }
        }
      ],
      "modified": "2026-10-24T10:50:25.102188613Z",
      "provider": "osv",
      "references": [
        "https://blog.zulip.com/2022/01/19/cve-2021-3866/",
        "https://github.com/zulip/zulip/commit/3eb2791c3e9695f7d37ffe84e0c2184fae665cb6",
        "https://huntr.dev/bounties/5f48dac5-e112-4b23-bbbf-cc00ba83bcf2"
      ],
      "provider_metadata": {
        "unresolved_ranges": [
          {
            "cpes": [
              "cpe:2.3:a:zulip:zulip:*:*:*:*:*:*:*:*"
            ],
            "vendor_product": "zulip:zulip",
            "extracted_events": [
              {
                "range": [
                  {
                    "last_affected": "4.8"
                  }
                ],
                "source": "CPE_RANGE"
              }
            ]
          }
        ]
      }
    },
    "related_cves": [
      {
        "value": "CVE-2021-3866",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 442137,
  "published_at": "2022-01-20T11:15:07.927+00:00"
}