CVE 2010-1422
WebKit in Apple Safari before 5.0 on Mac OS X 10.5 through 10.6 and Windows, and before 4.1 on Mac OS X 10.4, does not properly handle changes to keyboard focus that occur during processing of key press events, which allows remote attackers to force arbitrary key presses via a crafted HTML document.
See the 
CVE page on Mitre.org
for more details.
