CVE-2026-86411None▾ SunlitAn `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 …
▾ Sunlit zone — Low / medium · no exploitation signal
impact 2.8 · likelihood 0 · exploitation 0
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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.
curl >= 8.21.0 <= 8.21.0Refer to the linked advisories for vendor-supplied fixes and affected version ranges.
Connected by shared product, vendor, weakness, or advisory.
CVE-2026-107929Nonelocal interface connection reuse mixup
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