CVSS2
Attack Vector
LOCAL
Attack Complexity
MEDIUM
Authentication
SINGLE
Confidentiality Impact
COMPLETE
Integrity Impact
COMPLETE
Availability Impact
COMPLETE
AV:L/AC:M/Au:S/C:C/I:C/A:C
AI Score
Confidence
High
EPSS
Percentile
9.6%
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.
lists.freedesktop.org/archives/xorg/2004-June/000927.html
www.cansecwest.com/slides06/csw06-duflot.ppt
www.securityfocus.com/archive/1/454379/100/0/threaded
www.securityfocus.com/archive/1/454510/100/0/threaded
www.securityfocus.com/archive/1/454706/100/0/threaded
www.ssi.gouv.fr/fr/sciences/fichiers/lti/cansecwest2006-duflot-paper.pdf