CVE-2026-86411
FTP connection reuse inherits client-certificate
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.
INFO
Published Date :
Oct. 20, 2026, 8:17 p.m.
Last Modified :
Oct. 20, 2026, 8:17 p.m.
Remotely Exploit :
No
Source :
2499f714-1537-4658-8207-48ae4bb9eae9
Solution
- Avoid reusing FTP control connections with different security settings.
- Disable connection reuse for FTP control connections.
- Ensure TLS is properly configured for all FTP connections.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-86411.
| URL | Resource |
|---|---|
| https://curl.se/docs/CVE-2026-86411.html | |
| https://curl.se/docs/CVE-2026-86411.json | |
| https://hackerone.com/reports/3973190 |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-86411 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-86411
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-86411 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-86411 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
New CVE Received by 2499f714-1537-4658-8207-48ae4bb9eae9
Oct. 20, 2026
Action Type Old Value New Value Added 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. Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/86xxx/CVE-2026-86411.json">CVE-2026-86411</a> Added Reference https://curl.se/docs/CVE-2026-86411.html Added Reference https://curl.se/docs/CVE-2026-86411.json Added Reference https://hackerone.com/reports/3973190