Antivirus software plays the most significant role when it comes to protecting a computer against viruses, computer worms, and other malicious programs. They make it harder for these programs to infect a system by providing an extra layer of security, they help to ensure that these programs are detected as soon as possible in order to limit the damage that they can wreak on a system, and they are crucial in either quarantining or deleting these programs.
But the question is: how do antivirus programs work? How are they able to detect malicious programs? And is there a way in which they can be evaded? Here is what you should know about how antivirus software works and how a hacker can design malicious programs that can evade its detection systems.
How antivirus detects viruses and other malicious programs
Every virus is unique in terms of how it works, its code, and other distinguishing characteristics. Therefore, it is possible to form a unique signature of a virus, which essentially works the way a fingerprint works. As a result, once an antivirus software has this signature on record, it will be able to detect the malicious program as soon as it rears its head.
When antivirus software, like Kaspersky — you can see the full review about Kaspersky antivirus –, is either performing a quick scan or a complete scan, it is usually looking for these signatures. It compares the patterns of the programs that it comes across against a comprehensive database, and once it detects similarities, it earmarks the given program as a possible source of trouble. Consequently, it will take steps to either raise an alarm, neutralize it, or quarantine it in such a way that it cannot cause any harm.
Heuristic analysis and detection
However, to make sure that some viruses don’t slip through the signature scanning process, antivirus software creates ”families” of related malicious code. By doing so, the antivirus can be able to detect and neutralize mutations of known viruses. This is because by using this process, the software isn’t just looking for a single known signature, but for features or characteristics that may mimic the signature. This method allows it to widen the net and hence allowing it to offer better protection for your data and computer system.
For malware that passes the above tests, there is another way in which the antivirus software might try to ensnare it. It does so by observing the tendency of a program and the functions that it is targeting. Generally, if the virus seems to target the rootkit, in a way in which it seeks to take over the administrative functions of a computer, then the software may seek to stop it, and even eliminate it.
In order to boost their detection abilities, developers are starting to increasingly arm antivirus software with machine learning capabilities. With this method, the software can learn from past experiences and adjust its detection methods to such an extent that it can stop malicious programs even before they start to launch. When this method is combined with the above techniques, the chances of a malicious program slipping detection will be minimized.
How to evade antivirus software
The first way in which hackers create malware that evades detection by antivirus software is by coming up with new forms of viruses. Since antivirus software largely relies on databases to identify viruses, new viruses can avoid detection. Furthermore, there is also the fact that most people tend to forget updating their antivirus software. Since this means that the software will be relying on an outdated database, viruses can sneak through the software’s security systems.
The second way in which antivirus can be evaded is through mutation. With this technique, once the virus infects a computer, it immediately generates versions of itself that are not exactly similar to the original version. And since the antivirus will be relying on a particular signature to detect it, one or two of the mutated versions of the virus can evade detection.
The third method of evading antivirus detection is through obfuscation. With this method, the signature of the virus can be encrypted to such an extent that when compared to the database, the antivirus software does not come up with a match. Another method that has shown a degree of success is compression whereby the original virus is compressed. In such a case, antivirus software that heavily relies on signature-based detection can fail to detect the compressed version of the virus.
Based on the various ways in which antivirus software can be evaded, it is clear that relying on only one detection technique is not enough. For the ultimate protection, you need a strong antivirus program that employs multiple strategies when it comes to detecting viruses.