This tool uses CVE-2016-8740 to crash servers running Apache HTTPD 2.4.17 - 2.4.23 that support HTTP2. It crashes these servers by forcing them to allocate insanely large amounts of RAM, making the computer unuasable.

It can be downloaded here (you will need to run it from the command line)

Usage:

apachedos [target] [target port]