Trojan.Dozer is a Trojan virus that performs distributed denial of service (DDoS) attacks. It arrives in an spam email attachment and enters a computer as pxdrv.nls file. Once active, the Trojan connects to certain IP addresses through the following ports: 53, 80, 443. It opens a backdoor allowing the remote attacker to perform malicious actions. This Trojan virus can be updated, it may download additional files onto your computer. For example, it will download uregvs.nls file, which contains a list of targeted locations.

What is more, Trojan.Dozer attempts to replace the master boot record and searches for files with certain extensions. For example: .aspx, .java, .php, .pdf, .ppt, .rar, .txt and others. The Trojan virus then deletes all the found files that it can’t open and files with size of zero bytes.