{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "extracted_events": [
              {
                "introduced": "0"
              },
              {
                "fixed": "6.5.6"
              }
            ],
            "source": [
              "AFFECTED_FIELD",
              "REFERENCES"
            ]
          },
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "aba2569f7ed7a6bdbef816658fb6b7182531b751"
            }
          ],
          "repo": "https://github.com/tornadoweb/tornado",
          "type": "GIT"
        }
      ]
    }
  ],
  "aliases": [
    "GHSA-3x9g-8vmp-wqvf"
  ],
  "database_specific": {
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
      "CWE-200"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/49xxx/CVE-2026-49853.json"
  },
  "details": "Tornado is a Python web framework and asynchronous networking library. Prior to 6.5.6, SimpleAsyncHTTPClient shallow-copied redirected requests and removed only the Host header, leaving Authorization, auth_username, auth_password, and auth_mode in place when a redirect changed scheme, host, or port. This issue is fixed in version 6.5.6.",
  "id": "CVE-2026-49853",
  "modified": "2026-07-17T03:41:37.789037929Z",
  "published": "2026-07-14T20:41:32.075Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/tornadoweb/tornado/releases/tag/v6.5.6"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/49xxx/CVE-2026-49853.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/tornadoweb/tornado/security/advisories/GHSA-3x9g-8vmp-wqvf"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-49853"
    },
    {
      "type": "FIX",
      "url": "https://github.com/tornadoweb/tornado/commit/aba2569f7ed7a6bdbef816658fb6b7182531b751"
    },
    {
      "type": "FIX",
      "url": "https://github.com/tornadoweb/tornado/pull/3626"
    }
  ],
  "schema_version": "1.8.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Tornado: Authorization header forwarded across cross-origin redirects in SimpleAsyncHTTPClient"
}