WriteBlob assertion failed

[schumilo]

Prerequisites

• I have written a descriptive issue title
• I have verified that I am using the latest version of ImageMagick
• I have searched open and closed issues to ensure it has not already been reported

Description

Assertion fail in MagickCore/blob.c:5396: WriteBlob.

lt-magick: MagickCore/blob.c:5396: WriteBlob: Assertion `image != (Image *) NULL' failed.
Aborted (core dumped)

Found with a modified version of the kAFL fuzzer (https://github.com/RUB-SysSec/kAFL).

Credits: Sergej Schumilo, Cornelius Aschermann (Ruhr-Universität Bochum)

Steps to Reproduce

./magick assert_1 /dev/null 

assert_1.zip

System Configuration

• ImageMagick version: ImageMagick 7.0.7-29 Q16 x86_64 2018-04-30
• Environment (Operating system, version and so on): Ubuntu 16.04.4 LTS
• Additional information:

[urban-warrior]

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 @ https://www.imagemagick.org/download/beta/ by sometime tomorrow.

[nohmask]

This was assigned CVE-2018-16749.