It is possible to move image files to file with any extension in anyįolder by using ImageMagick's 'msl' pseudo protocol. $ convert delete_file.mvg out.png # deletes /tmp/delete.txt Image over 0,0 0,0 'ephemeral:/tmp/delete.txt' It is possible to delete files by using ImageMagick's 'ephemeral' pseudo protocol which deletes files after reading: delete_file.mvg push graphic-context Pop graphic-context the following then makes an http request to $ convert ssrf.mvg out.png 3. It is possible to make HTTP GET or FTP request: ssrf.mvg push graphic-context For svg PoC ImageMagick's svg parser should be used, not rsvg.Īll other issues also rely on dangerous ImageMagick feature of externalįiles inclusion from any supported protocol in formats like svg and mvg. (or curl) should be installed on the system for successful PoCĮxecution. Sources from 6 and 7 branches all are vulnerable. Ubuntu 14.04 and OS X, latest system packages (ImageMagick 6.9.3-7 Q16 InĪddition, ImageMagick's tool identify is also vulnerable, so it can'tīe used as a protection to filter file by it's content and createsĪdditional attack vectors (e.g. You can renameĮxploit.mvg to exploit.jpg or exploit.png to bypass file type checks. ImageMagick tries to guess the type of the file by it's content, soĮxploitation doesn't depend on the file extension. Images and uses default delegates.xml / policy.xml, may be vulnerable toĮxample execution $ convert exploit.mvg out.png Result, any service, which uses ImageMagick to process user supplied ImageMagick, see below), maybe some others - which allow to includeĮxternal files from any supported protocol including delegates.
This file format and idea of the local file read vulnerability in Svg, mvg (thanks to Stewie for his research of The most dangerous part is ImageMagick supports several formats like (wget or curl should be installed)ĭrwxr-xr-x 6 user group 204 Apr 29 23:08.
It is possible to pass the value likeĪnd execute unexpected 'ls -la'. Where %M is the actual link from the input. One of the default delegate's command is used to handle https requests: "wget" -q -O "%o" "https:%M" Due to insufficient %M param filtering it is possible to conduct shell command injection. It is implemented as a system() with command string ('command') from the config file delegates.xml with actual value for different params (input/output filenames etc). ImageMagick allows to process files with external libraries.
#Imagemagic png code#
Insufficient filtering for filename passed to delegate's command allows remote code execution during conversion of several file formats. CVE-2016-3714 - Insufficient shell characters filtering leads to(potentially remote) code execution ImageMagick: Multiple vulnerabilities in image decoder 1. We've reported these issues to developers of ImageMagick and they made a fix for RCE in sources and released new version (6.9.3-9 released changelog), but this fix seems to be incomplete. Nikolay Ermishkin from the Mail.Ru Security Team discovered several vulnerabilities in ImageMagick.
The below policy.xml example will disable the coders EPHEMERAL, URL, MVG, and MSL. The global policy for ImageMagick is usually found in “/etc/ImageMagick”.
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