CVE-2006-6730: Netbsd

Medium severity, CVSS 6.6. EPSS: 0.3% chance of exploitation in the next 30 days.

OpenBSD and NetBSD permit usermode code to kill the display server and write to the X.Org /dev/xf86 device, which allows local users with root privileges to reduce securelevel by replacing the System Management Mode (SMM) handler via a write to an SMRAM address within /dev/xf86 (aka the video card memory-mapped I/O range), and then launching the new handler via a System Management Interrupt (SMI), as demonstrated by a write to Programmed I/O port 0xB2.

Affected products

• Netbsd Netbsd: version 2.0.4 only
• OpenBSD OpenBSD: any version

Published 2006-12-26. Last modified 2026-06-16.