{"id":"CVE-2026-87861","state":"PUBLISHED","title":"cross-origin reuse of a Negotiate connection","description":"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.","publishedAt":"2026-10-20T20:09:28.592Z","updatedAt":"2026-10-30T11:55:20.837Z","severity":{"score":9.1,"label":"Critical","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N","source":"CISA-ADP"},"assigner":"curl","products":["curl curl"],"affected":[{"vendor":"curl","product":"curl","defaultStatus":"unaffected","versions":[{"version":"8.22.0","status":"affected","lessThanOrEqual":"8.22.0","versionType":"semver"},{"version":"8.21.0","status":"affected","lessThanOrEqual":"8.21.0","versionType":"semver"}]}],"references":["https://curl.se/docs/CVE-2026-87861.json","https://curl.se/docs/CVE-2026-87861.html","https://hackerone.com/reports/3972094"],"weaknesses":["CWE-201"],"ingestedAt":"2026-10-30T12:04:06.347Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/87xxx/CVE-2026-87861.json","commit":"e25d4a9cb7ccf6a7c7ca2498563a5909593766fe","baselineCommit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-87861","state":"PUBLISHED","datePublished":"2026-10-20T20:09:28.592Z","dateUpdated":"2026-10-30T11:55:20.837Z","assignerShortName":"curl","assignerOrgId":"2499f714-1537-4658-8207-48ae4bb9eae9","dateReserved":"2026-09-09T13:17:34.696Z"},"containers":{"cna":{"title":"cross-origin reuse of a Negotiate connection","descriptions":[{"lang":"en","value":"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."}],"affected":[{"vendor":"curl","product":"curl","defaultStatus":"unaffected","versions":[{"version":"8.22.0","status":"affected","lessThanOrEqual":"8.22.0","versionType":"semver"},{"version":"8.21.0","status":"affected","lessThanOrEqual":"8.21.0","versionType":"semver"}]}],"references":[{"url":"https://curl.se/docs/CVE-2026-87861.json","name":"json"},{"url":"https://curl.se/docs/CVE-2026-87861.html","name":"www"},{"url":"https://hackerone.com/reports/3972094","name":"issue"}],"problemTypes":[{"descriptions":[{"lang":"en","description":"CWE-201 Information Exposure Through Sent Data"}]}],"providerMetadata":{"shortName":"curl","orgId":"2499f714-1537-4658-8207-48ae4bb9eae9","dateUpdated":"2026-10-20T20:09:28.592Z"},"credits":[{"lang":"en","value":"Axel Mierczuk","type":"finder"},{"lang":"en","value":"Stefan Eissing","type":"remediation developer"}]},"adp":[{"title":"CISA ADP Vulnrichment","references":[{"url":"https://hackerone.com/reports/3972094","tags":["exploit"]}],"metrics":[{"cvssV3_1":{"scope":"UNCHANGED","version":"3.1","baseScore":9.1,"attackVector":"NETWORK","baseSeverity":"CRITICAL","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N","integrityImpact":"HIGH","userInteraction":"NONE","attackComplexity":"LOW","availabilityImpact":"NONE","privilegesRequired":"NONE","confidentialityImpact":"HIGH"}},{"other":{"type":"ssvc","content":{"timestamp":"2026-10-30T11:54:54.295912Z","id":"CVE-2026-87861","options":[{"Exploitation":"poc"},{"Automatable":"yes"},{"Technical Impact":"total"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-201","type":"CWE","lang":"en","description":"CWE-201 Insertion of Sensitive Information Into Sent Data"}]}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-10-30T11:55:20.837Z"}}]}}}