>From the simple.xcf file, 0x004ABABC will overwrite eip.
Tested on Windows XP SP3 and Windows 7 x64.
Fixed in the current release IrfanView 4.35: [1]
Shellcode from [2]
Old version installer at [3] [4].
[1] http://www.irfanview.com/main_history.htm
[2] http://code.google.com/p/win-exec-calc-shellcode/
[3] http://gd.tuwien.ac.at/graphics/irfanview/plugins/irfanview_plugins_433_setup.exe
[4] http://gd.tuwien.ac.at/graphics/irfanview/iview433_setup.exe
PoC: http://www.exploit-db.com/sploits/23288.tar.gz