Heap-based buffer overflow in the intu-help-qb (aka Intuit Help System Async Pluggable Protocol) handlers in HelpAsyncPluggableProtocol.dll in Intuit QuickBooks 2009 through 2012, when Internet Explorer is used, allows remote attackers to cause a denial of service (memory corruption) or possibly execute arbitrary code via a URI with a % (percent) character as its (1) last or (2) second-to-last character.
