ImageMagick before 7.0.8-55 has a use-after-free in DestroyStringInfo in MagickCore/string.c because the error manager is mishandled in coders/jpeg.c.
https://github.com/ImageMagick/ImageMagick/issues/1641
https://github.com/ImageMagick/ImageMagick/compare/7.0.8-54...7.0.8-55
https://github.com/ImageMagick/ImageMagick/commit/39f226a9c137f547e12afde972eeba7551124493