endless loop in ReadCAPTIONImage

[noirfate]

Version: ImageMagick 7.0.7-3 x86-64

I add a crafted font in ~/.config/ImageMagick/type.xml

 format="ttf"
 name="test"
 fullname="test font"
 family="URW Gothic"
 glyphs="/root/test.ttf"

and then run

magick -background lightblue -fill blue -font test -size 480x360 caption:'hello world' 1.gif

magick will always occupy 100% CPU. After I took a look, it maybe enter a endless loop in ReadCAPTIONImage.

you can get the font from https://github.com/noirfate/test/blob/master/test.ttf

[mikayla-grace]

Thanks for the problem report. We can reproduce it and will have a patch to fix it in GIT master branch @ https://github.com/ImageMagick/ImageMagick later today. The patch will be available in the beta releases of ImageMagick @ http://www.imagemagick.org/download/beta/ by sometime tomorrow.

[nohmask]

This was assigned CVE-2017-14741.