Do you REALLY need to know the difference between malware types?

Explaining Malware Types is Hard To Do

One of the stranger perils of being a technical writer involves being ambushed at odd moments by people demanding on-the-spot explanations of complex technical concepts.  I was out on the town one night and somehow found myself having to explain to a not-too-tech-savvy friend how to differentiate between a virus, a trojan and a worm.

After patiently listening to a lengthy, rambling answer, my friend thought it over for a minute and then asked, “So, why should I care? Why is this important to me? Do I really need to know the difference between different types of malwares?

My automatic reaction was to say, “Of course you need to!” – but to my surprise,  I couldn’t coherently express why I felt that way (though to be fair,  I was having trouble thinking clearly about anything that night).

Thinking it over in the sober light of day,  I realized that he’d actually asked a pretty good question. For most computer users, the difference between malware types is academic and irrelevant – at least,  right up until their computer gets infected. If everything’s working just fine, why in the world should they be able to distinguish between an exploit and a backdoor?

A Technical Person’s Answer

To get a expert’s opinion on this,  I relayed my friend’s question to an Analyst in our Response Lab. His reply was (and I’m paraphrasing here):

“Yes,  so that if anything happens, you’d know how the computer got infected, how to deal with the infection, and how to prevent it from spreading.”

Now, that’s the condensed version of a technical person’s answer. The real answer was actually a long, in-depth and detailed explanation covering how certain malware types had specific behaviors and particular vectors for distribution, as well as recommendations for dealing with particular types of infection.

And that there was the problem in a nutshell – it’s a lot of information to absorb. It was a thorough answer, but not an easy one to communicate to people with little interest in technicalities.  Some parts of the explanation also assumed more computer knowledge than most users would probably have or want.

Having said that, I thought the condensed version of our Analyst’s answer seemed like a helpful, ‘user-friendly’ answer. It summarizes all the main points effectively, puts it in a context most users would understand  and – this is important – it isn’t long-winded. I’ll come back to this again a little later.

Why A User Doesn’t Need To Know Malware Types

Trying to find a simple, all-encompassing answer to my friend’s question made me wonder if he really had a point and that users didn’t really need to know something as technical as malware types. So I decided to turn the question around and ask:

“Are there any cases in which ‘the average user’ doesn’t need to know the difference between malware types?”

The following four scenarios were the only ones I could think of where knowing malware types wouldn’t be helpful (if you can think of others, feel free to leave a comment). Of course,  I included some reasons why I think knowing malware types would be helpful even in these situations.

  1. I don’t do anything that might harm my computer.

    If you can honestly claim this, you’re probably what I’d call an Exemplary User: someone who diligently updates the operating system and programs, never installs programs or uses removable media without thoroughly vetting it first, doesn’t download from untrusted sources and basically, just does computer security right.

    An Exemplary User can laugh with scorn at looming malware outbreaks.  If this describes you, great! You can stop reading now. (Heck, you probably know the malware types already, anyway).

    Since the vast majority of users will never qualify for Exemplary Userhood however (myself included), the second best scenario is:

  2. MY computer can’t be infected.

    No, I’m not starting a PC versus Mac debate. What I mean is that even if malware does get onto your computer, it needs to find a suitable environment before it can have an effect. A Linux virus that somehow manages to get onto a Windows machine usually can’t do anything except blush sheepishly. Ditto for a backdoor that uses HTTP to connect to a remote site but ends up on a standalone computer without Internet acess.

    If your computer happens to be set up so that the majority of malware doesn’t target it or affect it (now you can start the PC/Mac debate), then our query becomes moot. Again, congratulations!

    Of course, most people have very little choice in the kind of operating system or programs they have on their computer, particularly business users. Even home users usually have to consider familiarity and affordability over specifically tailoring their computer to be malware resistant. To fix that, most users use antivirus protection. Which leads to reason 3:

  3. Why worry? My antivirus will remove it.

    Actually, since I work for a computer security company, I’d reeeaaally like it if more people could claim this. And hey – shameless plug – our Internet Security is doing pretty well in independent tests!

    Unfortunately, this solution isn’t 100% bulletproof, especially if you’re not an Exemplary User or are just plain unlucky.  Sometimes, the antivirus doesn’t catch the malware. Or it makes an error and the wrong file get fingered, causing all sorts of mayhem. Worse still, the antivirus turns out to be rogueware.

    In other words, the program you’re depending on to sort out all the problems….doesn’t. What then? Ah, then we move on to reason 4:

  4. Not my department. (IT/Tech Support/the computer guy) will just clean out any infection for me.

    OK, so the person fixing an infected computer should be the one with the technical knowledge, true. That person may not be the user, true. If you have someone dependable, willing and trustworthy, who can fix anything that goes wrong…can I have their number? Such a person is a godsend. Treasure him/her.

    Still, even if you’re that lucky, it’s often a great help to the actual technician if the user can pinpoint the probable cause. Knowing what type of dastardly program is screwing around with the computer gives the technician a good place to start investigating, and maybe also some idea of how to fix it.

    Or, to use an analogy, it’s the difference between driving to a workshop and telling the mechanic, “My car’s making a funny sound”, and saying, “The fan belt’s busted.”‘

And the Conclusion Is…

If you’re not in one of the 4 ‘Ideal Situations’ listed above, then it would probably be helpful for you to know the different kinds of malicious programs that can damage your computer, because…well, refer to condensed Analyst’s answer above.

Realistically though, learning about malware types, even superficially, requires investing time and energy that not every user can spare – which is why technical writers (ahem) have to find ways of communicating these concepts in ways that are interesting and easily accessible for everyone. Which brings us back to the condensed Analyst’s answer. It’s short, to the point and gives just enough information without being overwhelming. And if more information is asked for, well that’s the time to start going in-depth.

Personally, I like it – but since my part of my work deals with malware types anyway, I freely admit to being biased about this. So really, the best people to evaluate how useful that answer is – You, dear reader. So how about it? Do you think the condensed Analyst’s answer is a helpful, informative reply?


Oh and since we’re on the topic, here are the Types F-Secure uses to classify the samples – the good, the bad and the merely suspicious. You can also find plenty of other sites with excellent information on this topic – for example, has great articles explaining how trojans, viruses and worms work.

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Why Cameron hates WhatsApp so much

It’s a well-known fact that UK’s Prime Minister David Cameron doesn’t care much about peoples’ privacy. Recently he has been driving the so called Snooper’s Charter that would give authorities expanded surveillance powers, which got additional fuel from the Paris attacks. It is said that terrorists want to tear down the Western society and lifestyle. And Cameron definitively puts himself in the same camp with statements like this: “In our country, do we want to allow a means of communication between people which we cannot read? No, we must not.” David Cameron Note that he didn’t say terrorists, he said people. Kudos for the honesty. It’s a fact that terrorist blend in with the rest of the population and any attempt to weaken their security affects all of us. And it should be a no-brainer that a nation where the government can listen in on everybody is bad, at least if you have read Orwell’s Nineteen Eighty-Four. But why does WhatsApp occur over and over as an example of something that gives the snoops grey hair? It’s a mainstream instant messenger app that wasn’t built for security. There are also similar apps that focus on security and privacy, like Telegram, Signal and Wickr. Why isn’t Cameron raging about them? The answer is both simple and very significant. But it may not be obvious at fist. Internet was by default insecure and you had to use tools to fix that. The pre-Snowden era was the golden age for agencies tapping into the Internet backbone. Everything was open and unencrypted, except the really interesting stuff. Encryption itself became a signal that someone was of interest, and the authorities could use other means to find out what that person was up to. More and more encryption is being built in by default now when we, thanks to Snowden, know the real state of things. A secured connection between client and server is becoming the norm for communication services. And many services are deploying end-to-end encryption. That means that messages are secured and opened by the communicating devices, not by the servers. Stuff stored on the servers are thus also safe from snoops. So yes, people with Cameron’s mindset have a real problem here. Correctly implemented end-to-end encryption can be next to impossible to break. But there’s still one important thing that tapping the wire can reveal. That’s what communication tool you are using, and this is the important point. WhatsApp is a mainstream messenger with security. Telegram, Signal and Wickr are security messengers used by only a small group people with special needs. Traffic from both WhatsApp and Signal, for example, are encrypted. But the fact that you are using Signal is the important point. You stick out, just like encryption-users before. WhatsApp is the prime target of Cameron’s wrath mainly because it is showing us how security will be implemented in the future. We are quickly moving towards a net where security is built in. Everyone will get decent security by default and minding your security will not make you a suspect anymore. And that’s great! We all need protection in a world with escalating cyber criminality. WhatsApp is by no means a perfect security solution. The implementation of end-to-end encryption started in late 2014 and is still far from complete. The handling of metadata about users and communication is not very secure. And there are tricks the wire-snoops can use to map peoples’ network of contacts. So check it out thoroughly before you start using it for really hot stuff. But they seem to be on the path to become something unique. Among the first communication solutions that are easy to use, popular and secure by default. Apple's iMessage is another example. So easy that many are using it without knowing it, when they think they are sending SMS-messages. But iMessage’s security is unfortunately not flawless either.   Safe surfing, Micke   PS. Yes, weakening security IS a bad idea. An excellent example is the TSA luggage locks, that have a master key that *used to be* secret.   Image by Sam Azgor

November 26, 2015
Secure Wordpress site, mobile blogging, tablet by the bay

This is why you need to protect your WordPress username and password

If you run a Wordpress site, you know that criminals around the world would love to use it to spread malware. Last month, F-Secure Labs spike in "Flash redirectors" that automatically redirect the visitor to a site with the goal of infecting them with malware, in this case the Angler exploit kit. The source was compromised websites -- specifically Wordpress sites. This isn't a new find for the Labs but what is unique is one of the tactics of the attack -- seeking out Wordpress usernames. Why? "After obtaining the username, the only thing that the attacker would need to figure out is the password," Patricia from The Labs explains. "The tool used by the attacker attempted around 1200 passwords before it was able to successfully login." If you happen to have one of those passwords, bam. You site is serving up malware, which is not only harmful to your visitors, it can cost you tons of traffic as Google delists you. Keeping your server and plugins up to date is essential for avoiding most attacks. Beyond that, this attack points to the need to both protect your Wordpress username AND always use a unique, strong password. "Furthermore, in order to defend against this kind of WordPress attack, you should not use a WordPress admin account for publishing anything," Patricia notes. You can also protect your server from enumeration attacks that discover the usernames of your bloggers. To see how to do that, visit our News from the Labs blog. It's pretty amazing what people can figure out about you with just your login and password. But when you're running a website, which can be part or all of your livelihood, the only way to keep from handing criminals the key to your front door is to make sure your password can't be figured out by anyone but you. And turn on two-step authentication if you haven't already. Cheers, Jason

November 26, 2015

POLL – Is it OK for security products to collect data from your device?

We have a dilemma, and maybe you want to help us. I have written a lot about privacy and the trust relationship between users and software vendors. Users must trust the vendor to not misuse data that the software handles, but they have very poor abilities to base that trust on any facts. The vendor’s reputation is usually the most tangible thing available. Vendors can be split into two camps based on their business model. The providers of “free” services, like Facebook and Google, must collect comprehensive data about the users to be able to run targeted marketing. The other camp, where we at F-Secure are, sells products that you pay money for. This camp does not have the need to profile users, so the privacy-threats should be smaller. But is that the whole picture? No, not really. Vendors of paid products do not have the need to profile users for marketing. But there is still a lot of data on customers’ devices that may be relevant. The devices’ technical configuration is of course relevant when prioritizing maintenance. And knowing what features actually are used helps plan future releases. And we in the security field have additional interests. The prevalence of both clean and malicious files is important, as well as patterns related to malicious attacks. Just to name a few things. One of our primary goals is to guard your privacy. But we could on the other hand benefit from data on your device. Or to be precise, you could benefit from letting us use that data as it contributes to better protection overall. So that’s our dilemma. How to utilize this data in a way that won’t put your privacy in jeopardy? And how to maintain trust? How to convince you that data we collect really is used to improve your protection? Our policy for this is outlined here, and the anti-malware product’s data transfer is documented in detail in this document. In short, we only upload data necessary to produce the service, we focus on technical data and won’t take personal data, we use hashing of the data when feasible and we anonymize data so we can’t tell whom it came from. The trend is clearly towards lighter devices that rely more on cloud services. Our answer to that is Security Cloud. It enables devices to off-load tasks to the cloud and benefit from data collected from the whole community. But to keep up with the threats we must develop Security Cloud constantly. And that also means that we will need more info about what happens on your device. That’s why I would like to check what your opinion about data upload is. How do you feel about Security Cloud using data from your device to improve the overall security for all users? Do you trust us when we say that we apply strict rules to the data upload to guard your privacy?   [polldaddy poll=9196371]   Safe surfing, Micke   Image by  

November 24, 2015