CVE-2018-20024: Canonical Ubuntu Linux

High severity, CVSS 7.5. EPSS: 3.2% chance of exploitation in the next 30 days.

LibVNC before commit 4a21bbd097ef7c44bb000c3bd0907f96a10e4ce7 contains null pointer dereference in VNC client code that can result DoS.

Affected products

• Canonical Ubuntu Linux: version 14.04 only; version 16.04 only; version 18.04 only; version 18.10 only
• Debian Debian Linux: version 8.0 only; version 9.0 only
• Libvnc Project Libvncserver: before 0.9.12 (fixed in 0.9.12)

Published 2018-12-19. Last modified 2026-06-17.