Secefa.d is a dangerous and complex Internet worm, which spreads to vulnerable computers by exploiting known Microsoft Internet Explorer and Microsoft Windows vulnerabilities. The infection process does not require any user interaction. Once executed, Secefa.d secretly installs itself to the system and runs a spreading routine. The worm’s payload is comprised of several harmful functions. Secefa.d terminates running antiviruses, firewalls, a few spyware removers, some security-related programs, several other applications and even some parasites. It alters the Windows registry in order to bypass and disable the Windows Firewall and some other system components and tools such as the Registry Edtior. Secefa.d also blocks access to popular security-related web sites. Furthermore, the worm can secretly download from the Internet and install other dangerous parasites as well as unsolicited, potentially harmful applications. Secefa.d also opens a back door, which provides the attacker with remote unauthorized access to the compromised computer. The intruder can control the system and steal user sensitive information. The worm automatically runs on every Windows startup.