CVE-2023-3777: Canonical Ubuntu Linux

High severity, CVSS 7.8. EPSS: 0.4% chance of exploitation in the next 30 days.

A use-after-free vulnerability in the Linux kernel's netfilter: nf_tables component can be exploited to achieve local privilege escalation. When nf_tables_delrule() is flushing table rules, it is not checked whether the chain is bound and the chain's owner rule can also release the objects in certain circumstances. We recommend upgrading past commit 6eaf41e87a223ae6f8e7a28d6e78384ad7e407f8.

Affected products

• Canonical Ubuntu Linux: version 14.04 only; version 16.04 only; version 18.04 only; version 20.04 only; version 22.04 only
• Debian Debian Linux: version 12.0 only
• Linux Linux Kernel: from 5.9, before 5.10.188 (fixed in 5.10.188); from 5.11, before 5.15.123 (fixed in 5.15.123); from 5.16, before 6.1.42 (fixed in 6.1.42); from 6.2, before 6.4.7 (fixed in 6.4.7)

Published 2023-09-06. Last modified 2026-06-17.