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Comment by DangerousPie | Hacker News Reader

Here is the test program, from http://www.openwall.com/lists/oss-security/2015/01/27/9

https://gist.github.com/koelling/ef9b2b9d0be6d6dbab63

To test your system, simply run this (but obviously only after making sure gistfile1.c is clean ;))

    wget https://gist.githubusercontent.com/koelling/ef9b2b9d0be6d6dbab63/raw/de1730049198c64eaf8f8ab015a3c8b23b63fd34/gistfile1.c
    gcc gistfile1.c -o CVE-2015-0235
    ./CVE-2015-0235

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I always laugh when people give you a URL to C code to test for remote code execution...

Why?

Reproducers are standard fare and it's not like the code in this case is obfuscated. Are magic code goblins going to come and invoke Ken Thompson's untrustable computing and make your computer install windows and join a botnet or something?

Because if you give someone a URL to C code and they run it, you have effective gotten them to remotely execute your code ;-)

You're piping random executables from the internet without even looking at them to see what they do if you run that command.

There's no pipe involved in the GPs posting. It downloads a source file and the post even points out to check the file before compiling. I actually copied and pasted the test code from the original advisory. Should I have typed it in with my own bare fingers to be more secure? I agree with your sentiment in general, you just picked the wrong example to bash here.

I was responding to the later posts who were confused as to why someone would laugh at seeing that. You're right that you said to check and I wasn't trying to bash that post at all.

That aside, I actually did type it into my disposable VM. The theory being that if there was something subtle, it would force me either to type it wrong and not be exploited due to cognitive blindness or I'd catch the problem and avoid it.

I've read too many IOCC entries and I probably am a bit paranoid.

The average Linux IT guy will not read the C code. Many of them wouldn't be able to really understand what it does either. And this is best case code is simple and easy to grok.

If you're not reading the code you can just as well curl-and-pipe it. However, we run so much code on our computers that is trusted-by-association (oh, that's from apache.org, that's probably safe!) that it probably does not matter anyways.

    > You're piping random executables from the internet
    > without even looking at them to see what they do if you
    > run that command

... and then in your profile:

    > Just another Perl hacker.

You audit every CPAN module you install, line by line, right?

I agree, it is funny, but we run code we can't even see all day long. This is only 38 LOC. Anyone who is going to run it, however, should make sure they understand it.

You know you can also read the source code right? Even if you are not proficient with c you can understand what it's doing.

As opposed to code in some other language?

Might as well throw a --no-check-certificate in there

Anyone know how reliable that test is? I've got a system reporting not vulnerable but I'm not sure what glibc it has.

glibc 2.18 and greater were already patched, but it wasn't recognized as an RCE vulnerability at the time. See the first bullet under the "Mitigating factors" section in the link.

You can check your libc version with:

  ldd --version

I've got a system reporting glibc 2.11, but the test reports 'not vulnerable'.

We have already started to patch servers at Cloudways. Our CTO Pere Hospital explains how: http://www.cloudways.com/blog/ghost-vulnerability-patching/

All due respect, I think "explains that" would be more accurate than "explains how" here

True that Dampier. I wish I could edit it :(

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