CVE-2021-44731: Canonical Snapd

High severity, CVSS 7.8. EPSS: 1% chance of exploitation in the next 30 days.

A race condition existed in the snapd 2.54.2 snap-confine binary when preparing a private mount namespace for a snap. This could allow a local attacker to gain root privileges by bind-mounting their own contents inside the snap's private mount namespace and causing snap-confine to execute arbitrary code and hence gain privilege escalation. Fixed in snapd versions 2.54.3+18.04, 2.54.3+20.04 and 2.54.3+21.10.1

Affected products

• Canonical Snapd: up to and including 2.54.2
• Canonical Ubuntu Linux: version 18.04 only; version 20.04 only; version 21.10 only
• Debian Debian Linux: version 10.0 only; version 11.0 only
• Fedoraproject Fedora: version 34 only; version 35 only

Published 2022-02-17. Last modified 2026-06-17.