CVE-2026-86411

critical · 9.1

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.

9.1

CVSS

0.4%

EPSS (exploit prob.)

38th

EPSS percentile

2026-10-20

Published

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

Weaknesses

CWE-488

References

https://curl.se/docs/CVE-2026-86411.html
https://curl.se/docs/CVE-2026-86411.json
https://hackerone.com/reports/3973190
https://hackerone.com/reports/3973190

Query this programmatically:

curl https://evil-db.io/api/v1/cve/CVE-2026-86411