Site keeps getting hacked

[Arboristsite]

I am at a loss. My site continuously gets hacked and we cannot go back on a old database. We have about 2 weeks of new content on the site since we have been hacked.
I am in need of somebody with good knowledge of vbulletin to help me out. I am sure its a sql injection. They keep covering up my home page. I have a main tech but he is often too busy to get right on my stuff. My sponsors are starting to get a little riled up and it is causing a ton of un needed stress.

Hack that happens:
1. main page changes generally to linkbacks.com
2. I get a few phantom Admins that show up.
3. I can use the site perfectly if I use tapatalk
4. My email works but the sites email notifications stopped working.

If anyone would like to help be a tech, I would be open to it. Please come with references. I have 13 years of work done on the site and I would hate to lose it. Trust but verify.

[ozzy47]

First you need to follow our advisory about deleting the install folder off your forums.

Then please read the following two blog posts:
http://www.vbulletin.com/forum/blogs...ve-been-hacked (http://www.vbulletin.com/forum/blogs/zachery/3993888-fixing-your-site-after-you-have-been-hacked)

http://www.vbulletin.com/forum/blogs...vbulletin-site (http://www.vbulletin.com/forum/blogs/zachery/3993849-best-practices-for-securing-your-vbulletin-site)

Also please see these recent security announcements:

vBulletin 4.1.x-4.2.x & All versions of vBulletin 5: http://www.vbulletin.com/forum/forum...-1-vbulletin-5 (http://www.vbulletin.com/forum/forum/vbulletin-announcements/vbulletin-announcements_aa/3991423-potential-vbulletin-exploit-vbulletin-4-1-vbulletin-5)
vBulletin 5.0.x patch released, for a different security issue: http://www.vbulletin.com/forum/forum...d-all-versions (http://www.vbulletin.com/forum/forum/vbulletin-announcements/vbulletin-announcements_aa/3993204-vbulletin-5-connect-security-patches-released-all-versions)