Congratulations. You found the actual exploit.

http://git.savannah.gnu.org/cgit/patch.git/tree/src/pch.c#n2...

patch calls /bin/ed. /bin/ed has a ! command that feeds stuff to /bin/sh. Feeding unreviewed patches to the patch command is actually arbitrary command execution.

This is particularly awesome if patch is being used by other programs (i.e. a CI pipeline or other contexts).

Given the sardonic and amusing way the rest of the page is written, my guess is that's a part of the joke.

Not sure if you're aware of that but it's a joke page made as a parody of the recent "branded vulnerability" craze. I would definitely advise against running random scripts from joke pages, especially through sudo. In that regard notice the "TODO" line from the script:

    #!/bin/sh
    # TODO: Backdoor this machine?
    modprobe pcspkr
    beep -l 1000 -r 3 -f 44000

> Is this an OpenSSL bug?

> No.

> How do I uninstall Linux?

> Please follow instructions.

Shirley it's not meant as a serious resource.

I don't see the need to qualify "curl | sudo bash" with it being a two line script for it to be problematical.

"curl | bash" or "curl | sudo bash" is problematical no matter how large or small the script.

Yes, I know some people say that it is no worse than downloading to a file and then running the file without reading the script, which is what almost everyone does anyway.

These people are wrong. Downloading to a file and running it from there is always better because if you notice something wonky sometime after running the script, it is easier to prove the script caused it if you saved a copy before running it.

If you "curl | bash" it and then you notice something bad has happened and you want to look at the script, you have to curl it again. But then how do you know that second curl gives the same script as the one you just executed? If I were distributing a malicious script, I would set up my server to serve a non-malicious script most of the time and just occasionally substitute my malware script, and it would only distribute the malware once for each IP address.

Either do "curl > file; bash < file" of "curl | tee file | bash" rather than "curl | bash" if you aren't interesting in examining the script before running it.