An open-source security audit program funded by the U.S. Department of Homeland Security has flagged a critical vulnerability in the X Window System (X11) which is used in Unix and Linux systems. A missing parentheses in a bit of code is to blame. The error can grant a user root access, and was discovered using an automated code-scanning tool.
The flaw has been fixed.
It was a change from this:
if (getuid() == 0 || geteuid != 0)
if (getuid() == 0 || geteuid() != 0)
The best part was the CVS comment:
Fri Mar 10 17:29:51 2006 UTC (7 weeks, 4 days ago) by deraadt:
proper geteuid calls because suse hires people who mistype things
From the article:
Coverity, the San Franciso-based company managing the project under a $1.25 million grant, described the flaw as the “biggest security vulnerability” found in the X Window System code since 2000.
The X Window System, also called X11 or X, provides the toolkit and protocol to build GUIs for Unix and Unix-like operating systems. It is used to provide windowing for bit-map displays.
Source: Yahoo News
Apparently OpenBSD already fixed this during a code-cleanup.