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    ]
  },
  "details": "libcurl might in some circumstances reuse the wrong connection when asked to\ndo an authenticated HTTP(S) request after a Negotiate-authenticated one, when\nboth use the same host.\n\nlibcurl features a pool of recent connections so that subsequent requests can\nreuse an existing connection to avoid overhead.\n\nWhen reusing a connection a range of criteria must be met. Due to a logical\nerror in the code, a request that was issued by an application could\nwrongfully reuse an existing connection to the same server that was\nauthenticated using different credentials.\n\nAn application that first uses Negotiate authentication to a server with\n`user1:password1` and then does another operation to the same server asking\nfor any authentication method but for `user2:password2` (while the previous\nconnection is still alive) - the second request gets confused and wrongly\nreuses the same connection and sends the new request over that connection\nthinking it uses a mix of user1's and user2's credentials when it is in fact\nstill using the connection authenticated for user1...",
  "id": "CVE-2026-5545",
  "modified": "2026-07-08T05:37:41.580837848Z",
  "published": "2026-05-13T08:27:26.065Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://curl.se/docs/CVE-2026-5545.html"
    },
    {
      "type": "WEB",
      "url": "https://curl.se/docs/CVE-2026-5545.json"
    },
    {
      "type": "WEB",
      "url": "https://hackerone.com/reports/3642555"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/5xxx/CVE-2026-5545.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-5545"
    }
  ],
  "schema_version": "1.7.5",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:H/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "wrong reuse of HTTP Negotiate connection"
}