Why did my antivirus software fail to detect a virus on my computer?

How does malware circumvent anti-malware software and infiltrate your computer? Even the greatest software cannot always protect you. Even with the most recent anti-virus tools, it is still possible to fall victim to malware. Let’s establish basic terminologies and then discuss safety precautions.

A software vulnerability is not negative in and of itself. It is comparable to a hole in a bathroom wall: as long as no one is looking through it, no harm is done.
Obviously, you would want to rectify the issue and plug the hole by installing software updates that eliminate the vulnerability. However, as long as no one has discovered the hole, you are not at risk. It shouldn’t be there, but as long as no one is aware of it, everything is fine.
An exploit is analogous to a person discovering a hole in your toilet and peering through it to observe your private activities. If the hole is large enough, the intruder can even reach in and grab personal items or flush the toilet when you are not looking.
A software vulnerability can examine your computer’s data, steal personal information such as your passwords, or use your machine to transmit spam without your knowledge.

What Function Does Security Software Serve?

Anti-malware programs are analogous to security officers with a large photo album of all the individuals known to peep through gaps in toilet walls. As soon as they spot a character from that book, they expel them (or at least alert you to their presence).
Obviously, the difficulty is that these police officers are only as effective as the information they possess. If the anti-virus officer does not have the image of the Peeping Tom discovered elsewhere this morning, he will be unable to identify him.
That’s why anti-malware software and its databases receive so many upgrades!
However, not all anti-malware software is equally effective and efficient, just as not all law enforcement officers are same. Some are better than others in perceiving particular types of things, while others receive superior data from their headquarters. Some anti-malware technologies are better than others in detecting particular threats. Some are simply incompetent.

Finding Holes

Unlike a bathroom wall, software vulnerabilities are frequently not evident or easy to discover. It’s not unusual for a vulnerability to exist for years before an exploit is developed.
To continue the “computer software is like a bathroom” analogy, it is quite difficult to locate the holes in your wall. Depending on the quality of the original builder, there may be holes that are difficult to locate, but these are typically located and repaired fast.
And here’s the frightening part: hackers are like someone who spends all day and night peering at your bathroom wall from the outside, hoping to locate a hole that no one has ever found before. It’s not a new hole; it’s always been there!
Or, perhaps, they will identify a new way to exploit a previously identified but unpatched vulnerability. In either case, as soon as they are successful, they produce malware that exploits the unpatched breach in your bathroom wall (the software on your computer).

Avoiding Vulnerabilities

The advice for avoiding software vulnerabilities remains unchanged.
  • Update your computer software regularly.
  • Keep your anti-malware tools and their databases up-to-date; this is typically accomplished automatically.
  • In certain situations, uninstall applications known to pose problems, such as Java and Flash Player. Thankfully, both are now largely redundant!
  • And, of course, do not invite a swarm of Peeping Toms onto your computer by opening risky attachments, executing questionable downloads, or visiting questionable websites.
  • Create backups of all your vital data, as well as a full system backup.
And despite all of this, there is still the potential that an unknown vulnerability will be discovered and exploited before the defenses are upgraded.
This is why reputable antivirus software includes a Behaviour Blocker. It monitors the operations of the applications for certain malicious behavior patterns and provides an alarm whenever something suspect occurs. Behaviour Blocker is capable of detecting nearly all types of malware, even without frequent online updates.