CVE-2020-7065: Canonical Ubuntu Linux

High severity, CVSS 8.8. EPSS: 4.9% chance of exploitation in the next 30 days.

In PHP versions 7.3.x below 7.3.16 and 7.4.x below 7.4.4, while using mb_strtolower() function with UTF-32LE encoding, certain invalid strings could cause PHP to overwrite stack-allocated buffer. This could lead to memory corruption, crashes and potentially code execution.

Affected products

• Canonical Ubuntu Linux: version 12.04 only; version 14.04 only; version 16.04 only; version 18.04 only; version 19.10 only; version 20.04 only
• Debian Debian Linux: version 10.0 only
• PHP PHP: from 7.3.0, before 7.3.16 (fixed in 7.3.16); from 7.4.0, before 7.4.4 (fixed in 7.4.4)
• Tenable Tenable.sc: before 5.19.0 (fixed in 5.19.0)

Published 2020-04-01. Last modified 2026-06-17.