CVE-2016-4053: Canonical Ubuntu Linux

Low severity, CVSS 3.7. EPSS: 14.4% chance of exploitation in the next 30 days.

Squid 3.x before 3.5.17 and 4.x before 4.0.9 allow remote attackers to obtain sensitive stack layout information via crafted Edge Side Includes (ESI) responses, related to incorrect use of assert and compiler optimization.

Affected products

• Canonical Ubuntu Linux: version 12.04 only; version 14.04 only; version 15.10 only; version 16.04 only
• Oracle Linux: version 6 only; version 7 only
• Squid-Cache Squid: version 3.0 only; version 3.1 only; version 3.1.0.1 only; version 3.1.0.2 only; version 3.1.0.3 only; version 3.1.0.4 only; …

Published 2016-04-25. Last modified 2026-06-17.