ImageMagick: Out-of-bounds write in ICON decoder due to incorrect loop

ImageMagick is free and open-source software used for editing and manipulating digital images. Prior to versions 6.9.13-50 and 7.1.2-25, an incorrect loop in the ICON decoder can result in an out of bounds heap write resulting in a crash. This issue has been patched in versions 6.9.13-50 and 7.1.2-25.