Microsoft Windows Explorer (explorer.exe) allows user-assisted remote attackers to cause a denial of service (CPU consumption) via a certain PNG file with a large tEXt chunk that possibly triggers an integer overflow in PNG chunk size handling, as demonstrated by badlycrafted.png.
osvdb.org/45521
www.securityfocus.com/archive/1/480594/100/0/threaded
www.securityfocus.com/archive/1/480706/100/0/threaded
www.securityfocus.com/archive/1/480827/100/0/threaded
www.securityfocus.com/archive/1/480854/100/0/threaded
www.securityfocus.com/archive/1/480864/100/0/threaded
www.securityfocus.com/bid/25816