CVE-2018-18653: Canonical Ubuntu Linux

High severity, CVSS 7.8. EPSS: 0.3% chance of exploitation in the next 30 days.

The Linux kernel, as used in Ubuntu 18.10 and when booted with UEFI Secure Boot enabled, allows privileged local users to bypass intended Secure Boot restrictions and execute untrusted code by loading arbitrary kernel modules. This occurs because a modified kernel/module.c, in conjunction with certain configuration options, leads to mishandling of the result of signature verification.

Affected products

• Canonical Ubuntu Linux: version 18.10 only

Published 2018-10-26. Last modified 2026-06-17.