The biggest security threat in 2008 was caused by the discovery of the Rustock.C, a backdoor Trojan that allows remote attackers to use the compromised computer as an anonymous proxy server. The rootkit has been in the wild since October 2007, but it took the industry six months to detect it and issue a fix. Rootkit malware is extremely difficult to remove, even when using specialized tools. It can not be removed by average computer users, so the best solution is installing an anti-virus utility.”]
Source: https://www.bitdefender.com/blog/hotforsecurity/2008-new-security-risks-lurking/