{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "source": "REFERENCES"
          },
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "5351c980dcec7ad385730efdf4e1f4338b24fdb6"
            },
            {
              "fixed": "9f7c7ab6f2924824e4a61a3b5c5c36475f4e25c6"
            }
          ],
          "repo": "https://github.com/aio-libs/aiohttp",
          "type": "GIT"
        }
      ]
    }
  ],
  "aliases": [
    "GHSA-966j-vmvw-g2g9"
  ],
  "database_specific": {
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
      "CWE-200"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/34xxx/CVE-2026-34518.json",
    "unresolved_ranges": [
      {
        "extracted_events": [
          {
            "fixed": "3.13.4"
          }
        ],
        "source": "AFFECTED_FIELD"
      }
    ]
  },
  "details": "AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. Prior to version 3.13.4, when following redirects to a different origin, aiohttp drops the Authorization header, but retains the Cookie and Proxy-Authorization headers. This issue has been patched in version 3.13.4.",
  "id": "CVE-2026-34518",
  "modified": "2026-08-05T03:30:26.296407143Z",
  "published": "2026-04-01T20:15:22.426Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/aio-libs/aiohttp/releases/tag/v3.13.4"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/34xxx/CVE-2026-34518.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/aio-libs/aiohttp/security/advisories/GHSA-966j-vmvw-g2g9"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-34518"
    },
    {
      "type": "FIX",
      "url": "https://github.com/aio-libs/aiohttp/commit/5351c980dcec7ad385730efdf4e1f4338b24fdb6"
    }
  ],
  "schema_version": "1.8.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:U",
      "type": "CVSS_V4"
    }
  ],
  "summary": "AIOHTTP: Cookie and Proxy-Authorization headers leaked on cross-origin redirect"
}