All vulnerabilities
CVE-2026-86411

curl: FTP connection reuse inherits client-certificate

curl curlLibraries & packages
CVSS
NoneNot scored
ExploitationNo known exploitationNot in CISA KEV, which does not prove it is unexploitedCISA KEV
Exploit odds (EPSS)0.14%Chance of exploitation activity in the next 30 days, higher than 3% 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

An ftp:// transfer configured with CURLUSESSL_NONE can reuse a pooled FTP control connection that a previous easy handle upgraded with STARTTLS and authenticated using a client certificate. The second handle performs neither a new TLS handshake nor a new FTP login, so the server continues to authorize it under the first handle's certificate identity.

Text from CVE List

Affected versions 1

  • curlaffected: 8.21.0 through 8.21.0CVE List

References 3