VDB

CVE-2026-87861

CVE-2026-87861 PUBLISHED CVSS 9.1 CRITICAL

Reported by curl · Published October 20, 2026

When using ambient user credentials, an HTTP request directed to one origin may be dispatched over a connection previously authenticated via Negotiate for a different origin, leaving the request's intended credentials unused.

Risk Scores

CVSS 3.1
9.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

Affected Products

VendorProductVersions
curlcurl8.22.0, 8.21.0
alpinecurl0
curlcurl8.22.0, 8.21.0

Timeline

  • CVE Published
  • Oct 14, 2026 PoC Published
  • Oct 21, 2026 EPSS Score
  • Oct 24, 2026 EPSS Score
  • Oct 25, 2026 EPSS Score
  • Oct 27, 2026 EPSS Score
  • Oct 29, 2026 EPSS Score
  • Oct 31, 2026 EPSS Score

References

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