CVE-2020-14346: Canonical Ubuntu Linux

High severity, CVSS 7.8. EPSS: 0.6% chance of exploitation in the next 30 days.

A flaw was found in xorg-x11-server before 1.20.9. An integer underflow in the X input extension protocol decoding in the X server may lead to arbitrary access of memory contents. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.

Affected products

• Canonical Ubuntu Linux: version 14.04 only
• Red Hat Enterprise Linux: version 6.0 only; version 7.0 only; version 8.0 only
• X.org X Server: before 1.20.9 (fixed in 1.20.9)

Published 2020-09-15. Last modified 2026-06-17.