I hope this isn't repetitive but please add to/update this (outdated) list of legitimate antimalware software
* AhnLab (V3)
* Antiy Labs (Antiy-AVL)
* Aladdin (eSafe)
* Avast! Antivirus
* Authentium (Command Antivirus)
* AVG Technologies (AVG)
* Avira (AntiVir)
* Cat Computer Services (Quick Heal)
* ClamAV
* Comodo
* CA Inc. (Vet)
* Doctor Web, Ltd. (DrWeb)
* Emsi Software GmbH (a-squared)
* Eset Software (ESET NOD32)
* Fortinet
* FRISK Software (F-Prot)
* F-Secure
* G DATA Software (GData)
* Hacksoft (The Hacker)
* Hauri (ViRobot)
* Ikarus Software (Ikarus)
* INCA Internet (nProtect)
* K7 Computing (K7AntiVirus)
* Kaspersky Lab (AVP)
* Malwarebytes Antimalware
* McAfee (VirusScan)
* Microsoft (Windows Defender)
* Norman (Norman Antivirus)
* Panda Security (Panda Platinum)
* PC Tools (PCTools)
* Check Point (Zone Alarm)
* Prevx
* Rising Antivirus
* Secure Computing (SecureWeb)
* Bitdefender
* Sophos
* ThreatTrack software (VIPRE)
* Symantec/Norton
* Trend Micro
* VirusBlockADA (VBA32)
* VirusBuster
* AhnLab (V3)
* Antiy Labs (Antiy-AVL)
* Aladdin (eSafe)
* Avast! Antivirus
* Authentium (Command Antivirus)
* AVG Technologies (AVG)
* Avira (AntiVir)
* Cat Computer Services (Quick Heal)
* ClamAV
* Comodo
* CA Inc. (Vet)
* Doctor Web, Ltd. (DrWeb)
* Emsi Software GmbH (a-squared)
* Eset Software (ESET NOD32)
* Fortinet
* FRISK Software (F-Prot)
* F-Secure
* G DATA Software (GData)
* Hacksoft (The Hacker)
* Hauri (ViRobot)
* Ikarus Software (Ikarus)
* INCA Internet (nProtect)
* K7 Computing (K7AntiVirus)
* Kaspersky Lab (AVP)
* Malwarebytes Antimalware
* McAfee (VirusScan)
* Microsoft (Windows Defender)
* Norman (Norman Antivirus)
* Panda Security (Panda Platinum)
* PC Tools (PCTools)
* Check Point (Zone Alarm)
* Prevx
* Rising Antivirus
* Secure Computing (SecureWeb)
* Bitdefender
* Sophos
* ThreatTrack software (VIPRE)
* Symantec/Norton
* Trend Micro
* VirusBlockADA (VBA32)
* VirusBuster