{"id":"CVE-2026-87861","title":"cross-origin reuse of a Negotiate connection","summary":"When using ambient user credentials, an HTTP request directed to one origin\nmay be dispatched over a connection previously authenticated via Negotiate for\na different origin, leaving the request's intended credentials unused.","severity":"none","cwe":["CWE-201"],"vendor":"curl","product":"curl","affected":["curl >= 8.22.0 <= 8.22.0","curl >= 8.21.0 <= 8.21.0"],"published":"2026-10-20","updated":"2026-10-20","sourceUpdated":"2026-10-20T20:09:28.592Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-87861","references":[{"url":"https://curl.se/docs/CVE-2026-87861.json","label":"json"},{"url":"https://curl.se/docs/CVE-2026-87861.html","label":"www"},{"url":"https://hackerone.com/reports/3972094","label":"issue"}],"tags":["cve.org"],"ingestedAt":"2026-10-20T21:19:21.287Z","slug":"CVE-2026-87861","body":"## Overview\n\nWhen using ambient user credentials, an HTTP request directed to one origin\nmay be dispatched over a connection previously authenticated via Negotiate for\na different origin, leaving the request's intended credentials unused.\n\n## Affected\n\n- `curl >= 8.22.0 <= 8.22.0`\n- `curl >= 8.21.0 <= 8.21.0`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":3,"depthScoreParts":{"impact":2.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}