Skip to content Skip to navigation Skip to footer

What Is Heuristic Analysis?

Heuristic Analysis Definition

What is heuristic analysis? Heuristic evaluation or analysis works by looking for commands and instructions not normally present in a benevolent application. For example, it may detect commands to deliver payloads often disguised within a Trojan horse virus or those used to distribute a worm virus throughout your network. 

Heuristic analysis can pinpoint a virus through the way it replicates as it spreads. It is also at the heart of user and entity behavior analytics (UEBA), which uses algorithms to study the behavior of users, routers, endpoints, and servers.

Heuristic Analysis Meaning: How Does Heuristic Analysis Work?

Heuristic analysis is done using a couple of different techniques:

Static Heuristic Analysis

Static heuristic analysis involves examining the source code of a program and comparing it to the source code of known viruses that have already been logged in a database. If enough of it matches what is in the database, the code gets flagged as a potential threat.

Dynamic Heuristic Analysis

Dynamic heuristic analysis uses a virtual machine, which acts as a sandbox. A sandbox is a safe, isolated environment in which a program can execute without affecting the rest of your system or network. With dynamic heuristic analysis, the sandbox environment allows the file to run, so you can see what it would do if it runs in a sensitive environment.

For example, during a dynamic heuristic analysis, the program under observation may self-replicate, try to stay within resident memory after executing, overwrite files, or do other things that viruses are often programmed to do.

Heuristic Analysis Definition: Advantages and Disadvantages of Heuristic Analysis

There are a few advantages and disadvantages to heuristic analysis, but despite the drawbacks, it is still a very powerful tool. 

Advantages

Heuristic analysis can detect more than just modified forms of current malicious programs. It can also detect previously unknown malicious programs. This is because it analyses the behavior of a potential threat instead of its file name.

This method of analysis also reduces the number of false positives because some behaviors are very specific to malware, and heuristic analysis can identify them, pinpointing the threat. For example, if a program tries to delete files that are needed by the operating system, it is most likely malicious. Heuristic analysis can detect this kind of behavior and flag the threat so it can be removed.

On the other hand, by merely examining the signature of a program and comparing it to those of known threats, the threat may slip away unnoticed, simply because it does not match a known threat. This is often the case when dealing with a zero-day or previously unknown threat. Heuristic analysis can flag the threat based on what it does, regardless of whether it has already been logged in a threat management system.

Disadvantages

Heuristic analysis is designed to detect known threat behavior. If the threat does not perform any action the threat detection technology has been programmed to recognize, it can slip under the radar.

To illustrate, suppose your antivirus software has been engineered to flag a program that tries to delete files your operating system needs but not files that decrypt themselves. In this case, if it comes across a self-decrypting file, it may not notice that it is a threat—even though this action is typical of threats.

There is also a chance that the antivirus/anti-malware software uses heuristic scanning based on a range of behavior that is too broad. In this heuristic analysis example, the process can result in mislabeling innocent files as threats. However, this is more common in older heuristic analysis programs, so if you have a newer one and it has been recently updated, chances are it uses modern techniques, which limit the number of false positives.

Heuristic Analysis vs. Heuristic Virus

It is easy to confuse the terms “heuristic analysis” and “heuristic virus.” However, in some ways, they can not be more different. A heuristic virus can be detected using heuristic analysis. For example, the malware known as Heur.Invader is designed to make changes to your system’s settings. Therefore, it can be detected using heuristic analysis.

Heuristic analysis, on the other hand, identifies programs or applications that behave suspiciously. In other words, heuristic analysis is a methodology used to identify a heuristic virus.

How Does Heuristic Analysis Help to Detect and Remove a Heuristic Virus?

Heuristic analysis detects and removes a heuristic virus by first checking files in your computer, as well as code that may be behaving in a suspicious manner. Once a potential threat has been identified, it gets flagged.

At this point, the threat can be removed from your system. The antivirus system can also quarantine the threat, which can give IT teams the opportunity to study it and gain a better understanding of what it is and how it works.

How To Run an Effective Heuristic Analysis

Thanks to modern antivirus software, it is relatively easy to run a heuristic analysis:

  1. Start up your device in safe mode.
  2. Once startup is complete, run an antivirus scan using your heuristically enabled anti-malware software.
  3. After the program has identified suspicious files, carefully check them to see if they are definitely ones you want to delete. It can sometimes help to Google the file name to see if others have come across it and how they have dealt with it.

How Can Fortinet Help?

The FortiGate Next-Generation Firewall (NGFW) uses heuristic analysis to identify suspicious behavior and then remove the threat from your system. FortiGate does this using machine learning algorithms that can detect anomalous behavior indicative of a threat. This gives it the ability to pinpoint zero-day attacks heuristically, honing in on behavior that typifies malware.

FortiGate is powered by an onboard processor that enables it to perform deep scans of data packets as they attempt to enter or exit your network. In this way, not only does it perform heuristic analysis, but it also does so in a way that does not negatively impact your throughput.

FAQs

What does heuristic analysis mean?

Heuristic analysis is a method of threat detection that works by looking for commands and instructions that would not normally be present in a benevolent application.

How does the heuristic technique work?

Heuristic analysis evaluates the actions of programs using a couple of different techniques. For example, you can use static heuristic analysis, which involves examining the source code and comparing it to the source code of known viruses. You can also use dynamic heuristic analysis, which uses a virtual machine that acts as a sandbox. With dynamic heuristic analysis, the sandbox environment allows the file to run, so you can see what it would do in a sensitive environment.

How does the heuristic method detect viruses?

Heuristic analysis detects and removes a heuristic virus by first checking files in your computer, as well as code that behaves in a suspicious manner. Once a potential threat has been identified, it gets flagged.