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Huge Number Of Sites Imperiled By Critical Image-Processing Vulnerability (arstechnica.com)
Dan Goodin, reporting for Ars Technica: A large number of websites are vulnerable to a simple attack that allows hackers to execute malicious code hidden inside booby-trapped images. The vulnerability resides in ImageMagick, a widely used image-processing library that's supported by PHP, Ruby, NodeJS, Python, and about a dozen other languages. Many social media and blogging sites, as well as a large number of content management systems, directly or indirectly rely on ImageMagick-based processing so they can resize images uploaded by end users. According to developer and security researcher Ryan Huber, ImageMagick suffers from a vulnerability that allows malformed images to force a Web server to execute code of an attacker's choosing. Websites that use ImageMagick and allow users to upload images are at risk of attacks that could completely compromise their security. "The exploit is trivial, so we expect it to be available within hours of this post," Huber wrote in a blog post. He went on to say: "We have collectively determined that these vulnerabilities are available to individuals other than the person(s) who discovered them. An unknowable number of people having access to these vulnerabilities makes this a critical issue for everyone using this software."
Because keeping exploits secret leads to an ostrich mentality. Companies often prefer to shoot the messenger rather than solve the problem.
Take your time.
Why are they much better alternatives?
The software written in (*) has no vulnerabilities?
Choosing a language does not really address security, because that choosing will affect how the programmer thinks about security and possibly the less experienced programmers will slack on "programming for safety" paradigm .. because the language does everything for the programmer.
For example:
Please have a look at fefe's gatling[1], an incredible fast http-server, with only very few security problems in the past - written entierly in "C". Also the funny thing is that certain of these highlevel languages will use bindings to these older libraries written in C.
So you will be bitten again.
From all information I overlook I can say, yes in "C" it is incredible easy to make simple errors with hugh consequences - choosing types for example. However "C"-programming can be made more secure with a strict application of certain rules especially on "forbidden" & dangerous constructions. The missconception why "C" is deemed as an insecure language is that much of the code in use stems from the "ancient" times, when such code was mostly not exposed to the raw unforgiving "force" of the internet.
Also there was not such a "zoo" for other different programming languages, so much of the software was implemented using "C". This effect is similar to todays "I use java now, I don't need to take care of security".
The different incarnations of "C" standards also play their part, similar to the "Perl-Mageddon" if you do not have a concise standard about how a programming language will be "interpreted" or "translated" you are deemed to introduce errors. Imagemagik is bloated & ancient, two aspects that are problematic. Fefe adheres to his own standards, that bloat and complexity are the real threats for security. (dietlibc vs. libc). And he is often correct on this topic.
[1] http://www.fefe.de/
Suggestion: read the article and details, before making assumptions. Because if you did, you would have see that that was done. A patch was created but apparently not complete. They also include two mitigation 'patches' (config) in the disclosure. Considering the seriousness of this exploit (even I could understand it - which makes it beyond trivial) the more attention this gets, the better.
From https://imagetragick.com/
April, 21 2016 - file read vulnerability report for one of My.Com services from https://hackerone.com/stewie received by Mail.Ru Security Team. Issue is reportedly known to ImageMagic team.
April, 21 2016 - file read vulnerability patched by My.Com development team
April, 28 2016 - code execution vulnerability in ImageMagick was found by Nikolay Ermishkin from Mail.Ru Security Team while researching original report
April, 30 2016 - code execution vulnerability reported to ImageMagick development team
April, 30 2016 - code execution vulnerability fixed by ImageMagick (incomplete fix)
April, 30 2016 - fixed ImageMagic version 6.9.3-9 published (incomplete fix)
May, 1 2016 - ImageMagic informed of the fix bypass
May, 2 2016 - limited disclosure to 'distros' mailing list
May, 3 2016 - public disclosure at https://imagetragick.com/
This bug has nothing to do with the language it's written in. It's a simple matter of failing to properly escape special characters when switching contexts (filename -> executable command). You can mess that up in any language.
Update your /etc/ImageMagick/policy.xml file so that it contains this (taken from http://imagetragick.com ) and restart corresponding daemons:
/> /> /> /> /> /> /> /> />
<policymap>
<policy domain="coder" rights="none" pattern="EPHEMERAL"
<policy domain="coder" rights="none" pattern="URL"
<policy domain="coder" rights="none" pattern="HTTPS"
<policy domain="coder" rights="none" pattern="MVG"
<policy domain="coder" rights="none" pattern="MSL"
<policy domain="coder" rights="none" pattern="TEXT"
<policy domain="coder" rights="none" pattern="SHOW"
<policy domain="coder" rights="none" pattern="WIN"
<policy domain="coder" rights="none" pattern="PLT"
</policymap>
You're safe now. The full fix is still being worked out.