How do websites get infected?

Having had got access to a website, hackers can insert the code to redirect users to Unwanted websites into all website pages, as well as leave special executable files, so-called Backdoors, which will in future allow them to perform any operation on files on server easily.

Such attacks set two challenges for a website antivirus: number one – “curing”, recovery of the initial state of the infected files, and number two – finding and eliminating of Backdoors.