All vulnerabilities
CVE-2026-87861

curl: cross-origin reuse of a Negotiate connection

curl curlLibraries & packages
CVSS
NoneNot scored
ExploitationNo known exploitationNot in CISA KEV, which does not prove it is unexploitedCISA KEV
Exploit odds (EPSS)0.29%Chance of exploitation activity in the next 30 days, higher than 20% of CVEs. Scored 23 Oct 2026FIRST EPSS
Fixed inNone listedNo source names a fixed version yet
Published20 Oct 2026Updated 20 Oct 2026CVE List

What fixes it

No source in this snapshot names a fixed version.

Description

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.

Text from CVE List

Affected versions 2

  • curlaffected: 8.22.0 through 8.22.0CVE List
  • curlaffected: 8.21.0 through 8.21.0CVE List

References 3