Wordpress site recently hacked and need help determining issue

This morning my site was down and I was advised by the server company that there is a very high load on the server: load average: 105.13, 134.02, 138.64

This is causing the server to run out of RAM, and swap space. Anytime I reboot the server immediately crashes and all the sites on the server also go down.

I was provided the below info:

root@ds1239 [~]# free -m
total used free shared buffers cached
Mem: 2009 1874 135 0 5 63
-/+ buffers/cache: 1805 203
Swap: 3999 2121 1878

Any idea of what type of hack would cause this? They are currently scanning the account for malware with maldet but as of now nothing has been found:
maldet(13179): {scan} 21172/35499 files scanned: 0 hits 0 cleaned

The server company is recommending I beef up the ram however I don't think that the ram is an immidiate issue as the site has been running smoothly up until this morning. It's a wordpress powered site and I know these are pretty vulnerable to attacks.

Any help would be greatly appreciated!

 

Would need access to log files at the very least. Finding an entry of an attack takes time.

 

Most likely it's just excess traffic or slow queries. Slow queries being the most likely, and the most likely cause is a poorly coded plugin. If you've added any new plugins to wordpress recently, the remove them - or better yet, simply disable all plugins for a short while to see if it remedies the situation, then re-enable one by one till you get the same problem.

Else, if you just bought a package of traffic to come to your website, and don't have any cache's running, then... well that's your problem.