CVE-2020-12663: Canonical Ubuntu Linux

High severity, CVSS 7.5. EPSS: 3.6% chance of exploitation in the next 30 days.

Unbound before 1.10.1 has an infinite loop via malformed DNS answers received from upstream servers.

Affected products

• Canonical Ubuntu Linux: version 18.04 only; version 19.10 only; version 20.04 only
• Debian Debian Linux: version 9.0 only; version 10.0 only
• Fedoraproject Fedora: version 31 only; version 32 only
• Nlnetlabs Unbound: before 1.10.1 (fixed in 1.10.1)
• Opensuse Leap: version 15.1 only; version 15.2 only

Published 2020-05-19. Last modified 2026-06-17.