CVE-2016-10027: Fedoraproject Fedora

Medium severity, CVSS 5.9. EPSS: 1.5% chance of exploitation in the next 30 days.

Race condition in the XMPP library in Smack before 4.1.9, when the SecurityMode.required TLS setting has been set, allows man-in-the-middle attackers to bypass TLS protections and trigger use of cleartext for client authentication by stripping the "starttls" feature from a server response.

Affected products

• Fedoraproject Fedora: version 25 only
• Ignite Realtime Smack: before 4.1.9 (fixed in 4.1.9)

Published 2017-01-12. Last modified 2026-06-17.