DNSChanger is a trojan that will change the infected system's Domain Name Server (DNS) settings, in order to divert traffic to unsolicited, and potentially illegal sites.
The trojan is usually a small file (about 1.5 kilobytes) that is designed to change the 'NameServer' Registry key value to a custom IP address. This IP address is usually encrypted in the body of a trojan. As a result of this change a victim's computer will contact the newly assigned DNS server to resolve names of different webservers.
Trojan.Win32.DNSChanger.al Lately we got a few samples of this trojan that were named 'PayPal-2.5.200-MSWin32-x86-2005.exe'. This trojan was programmed to change the DNS server name of a victim's computer to 220.127.116.11 address.
The Registry key that is affected by this trojan is: