Server Owners
All server owners serious about stopping hackers and cheaters should be blocking older clients.
This can be done by editing the setting in the mtaserver.conf file.
Check the latest client version numbers from here: https://nightly.multitheftauto.com/ver/
The Auto-update default: version number is the current release version.
The Max recommended/minclientversion: version number is the newest build which is available by automatic update. This revision is usually updated when a cheat gets blocked, so you can easily enforce patched clients.
The Auto-update nightly version number on that page is not relevant here, so forget you ever saw it
Put you chosen min client version into the mtaserver.conf like this:
<minclientversion>1.5.7-9.20447.0</minclientversion>
For competitive servers, it is also advisable to enable special detection (SD) #16, #31 and #32 in mtaserver.conf like this:
<enablesd>15,16,31,32</enablesd>
Other SD codes are available here: https://wiki.multitheftauto.com/wiki/Anti-cheat_guide (you can also find explanation on what each SD # detection helps prevent)
AC Panel resource
AC Panel is a helper resource to view/manage your servers anti-cheat settings (including easily switching minclient version) that may be useful to you:
https://community.multitheftauto.com/index.php?p=resources&s=details&id=6242