This one has happened to some of my design clients so far. You hire a designer, give access to your site, and suddenly you’re locked out of your site or you find out that there are spam links, malicious code, or other bugs coded into your site’s files.
Carry out the following:
If you are locked out of your site or find malware, contact your host immediately. The support staff will be able to help you regain access and track down the infected files. And if your host is halfway decent, they won’t charge you anything for it.
How to avoid this:
Also, be very cautious when hiring a designer from a foreign country. I’m not saying all of them will hijack your site, but most of these scams seem to come from overseas. On my hosting servers, I block hack attempts from countries overseas mostly India, China, Pakistan and Russia on occasions, be cautious and be sure to check references mentioned above.