We hang the server through PHP

Hello, dear habr-users. Quite a while ago, I wrote a PHP script called a fork-bomb and started testing it on various servers / hostings. To my surprise, the script worked on 90% of the companies I tested. I wrote about this bug to many companies, but a lot of time has passed, and it is still relevant.

How the script works

For a start, we check which of the functions we need are available on the server. There are 5 of them:
exec , shell_exec , system , is_resource , passthru .
I will not describe each function, if you are interested, I left links to them.

Then we just perform a fork request through the function, and if the server is vulnerable, then only a reboot will help it.

Than it threatens

')
Not only does the script hang the server, you can put it on the crown and an inexperienced administrator will search for a long time the reason why his server crashes right after the download. Experienced it does not cause problems, but still not nice.

Script itself

http://pastebin.com/NQvszGFq
Laid out the script on the paste, because Many users did not allow the antivirus, Swore at PHP-Shell.

Conclusion

Attention, all operations you perform at your own risk! The article is written for informational purposes.