GNOME gdk-pixbuf (aka GdkPixbuf) before 2.42.2 allows a denial of service (infinite loop) in lzw.c in the function write_indexes. if c-self_code equals 10, self-code_table[10].extends will assign the value 11 to c. The next execution in the loop will assign self-code_table[11].extends to c, which will give the value of 10. This will make the loop run infinitely.

This bug can, for example, be triggered by calling this function with a GIF image with LZW compression that is crafted in a special way.