CVE-2026-8286

A flaw was found in curl. When a new data transfer attempts to upgrade its connection using STARTTLS, it may incorrectly reuse an existing live connection. This reuse can occur even if the Transport Layer Security (TLS) configuration of the new transfer does not match the existing connection, potentially leading to an insecure connection being established.

This is an Important flaw as curl may establish an insecure connection when attempting to upgrade a transfer with STARTTLS, potentially reusing an existing connection with mismatched TLS configurations. This could lead to unexpected data exposure or compromise, particularly in environments where curl is used for sensitive data transfers and relies on STARTTLS for security.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.

Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.