CVE-2026-86411
Last modified
CVE-2026-86411 is a critical-severity vulnerability rated 9.1/10 on the CVSS scale. 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.. EPSS estimates a 0.15% chance of exploitation in the next 30 days.
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.
Metrics
Weakness Enumeration
Affected Software
Source: CNA advisory (CVE.org). NVD analysis pending.
| Vendor | Product | Versions |
|---|---|---|
| curl | curl | >= 8.21.0, <= 8.21.0 |
References
Timeline
- Published
- Last Modified
- Status
- Awaiting Analysis
Frequently Asked Questions
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How Strix Helps
- How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
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