CVE-2011-4408: Canonical Ubuntu Linux

Medium severity, CVSS 6.8. EPSS: 1.2% chance of exploitation in the next 30 days.

The Single Sign On Client (ubuntu-sso-client) for Ubuntu 11.04 and 11.10 does not properly validate SSL certificates when using HTTPS, which allows remote attackers to spoof a server and modify or read sensitive data via a man-in-the-middle (MITM) attack.

Affected products

• Canonical Ubuntu Linux: version 11.04 only; version 11.10 only

Published 2012-06-16. Last modified 2026-06-16.