CVE-2006-5173: Canonical Ubuntu Linux

Low severity, CVSS 2.1. EPSS: 0.4% chance of exploitation in the next 30 days.

Linux kernel does not properly save or restore EFLAGS during a context switch, or reset the flags when creating new threads, which allows local users to cause a denial of service (process crash), as demonstrated using a process that sets the Alignment Check flag (EFLAGS 0x40000), which triggers a SIGBUS in other processes that have an unaligned access.

Affected products

• Canonical Ubuntu Linux: version 5.10 only; version 6.06 only; version 6.10 only
• Linux Linux Kernel: from 2.4.0, up to and including 2.6.19

Published 2006-10-17. Last modified 2026-06-16.