There are a lot of free antivirus software and free versions of commercial anti-malwares. Can we really trust these free antivirus programs?

The same question about commercial antivirus software. Maybe they install backdoors on our computers?


  Maybe commercial or free anti-malware installs backdoors


Very true. Maybe they do.

However – there are a lot of technically experienced individuals who are in a position to check, either through monitoring unexpected connections outbound, or through reviewing the code, so we can have reasonable assurance that they don't.

But think about the alternative – we know that malware does install backdoors etc., so from a risk based perspective, which would you prefer? A control that you personally haven't vetted, but that many others approve, or a lack of control which leaves you open to malware.

Pretty simple. Trust isn't required – it's just up to you to balance the risk factors for your circumstances.

If you need any guidance, large companies use perimeter and desktop anti-virus and anti-malware, as well as anti-malware on laptops and other endpoints. It isn't cheap for them, so it is very much a risk based decision to spend that money.
