This is the second posting in a three-part series covering common threats a user may encounter.
This series serves as a rough and ready guide, highlighting key features and trends relevant to most users.
Viruses have always loomed large in users’ minds as the poster child of malicious programs – heck, we even call it the anti-virus industry. In the last 10 years or so however, the number of virus infections has nosedived; our Labs, which once dealt with viruses routinely, now sees a proper virus infection about once or twice a month. Today when people talk of ‘viruses’, more often than not what they’re describing is technically a trojan or a worm, and they’re using the term in a general, ‘any malware will do’ kind of way.
That’s not to say viruses are extinct; we still receive a small, if persistent, number of queries about viruses. This may be because many businesses, households and users (both in developed countries and in recently connected developing ones) still use old, out-dated, unpatched machines or programs, or haven’t yet developed a security-conscious habits.
Whatever the case, virus infections will probably still cling on to life for a weary day after, so let’s take a look at them.
The Merriam-Webster online dictionary’s bare-bones definition of a computer virus touches on important elements most users should know, so I’ll just elaborate a bit more on some key concepts:
Last week I compared a virus to a parasite, because not only does it ‘hide’ in another program, but also depends on its host to function. For the virus to run, the unsuspecting user must actively launch the infected program, which in turn launches the virus.
For this reason, virus writers usually create viruses that infect executable files (especially popular programs such as word processors or media files), which have a higher chance of being run; programs with files that get passed around a lot are extra attractive, since they can affect even more potential victims.
A good example is the Microsoft Office suite which, with their huge community of business and personal users, used to be a popular target for macro viruses. We still see queries related to this virus type, though thankfully far less than previously.
If you think of the common cold virus spreading from one person to another, you’ll have a pretty good idea of why this behavior can be so damaging. When a infected file is executed, it searches for and infects new files; if the newly infected files are launched, they find and infect new files in turn, like some evil Multi-Level Marketing operation. At worst, this pattern can lead to every targeted file on the system being infected.
The damage a virus can do by replicating and infecting new files is bad enough; its payload, a completely separate set of nasty actions, can be worse. The range of actions a virus can take is huge – connecting to a remote site, changing the desktop wallpaper, displaying silly notification messages, deleting data files…it really just depends on the virus author’s imagination and programming skills.
If you’re lucky, they’re not that good and you get failed viruses like Virus:W32/Stardust; if they’re good, then you get really nasty beasts like Virus:W32/Virut or Virus:W32/Sality.AA (one of the few viruses we still find regularly active).
With thousands of unique viruses out in the wild, antivirus companies find it necessary to divide them into sub-types. Unlike trojans though, viruses don’t fall into neat categories reflecting their actions; instead, they naturally fall into groupings based on technical differences in the way they infect a file – which is basically gobbledeegook to a user not interested in detailed analysis.
Gnerally, viruses can be divided into two groups – system infectors and file infectors. The majority of viruses are the latter and infect programs or data files. System infectors on the other hand write their malicious code to specific, critical sections of the hard disk containing the operating system, so that while the OS is running its normal routines, it’s also unintentionally executing the virus code.
Fortunately, for most users a virus’s classification is largely academic. For better or for worse, the sheer variety of possible effects each unique virus can have on a file or system makes it more practical to take each virus on a case by case basis.
So let’s go back to the original question that sparked off this series: do you really need to know if it’s a virus – as opposed to, say, a trojan or worm – infecting your computer?
Well, it helps to know because the two malware types tend affect your data and computer in different ways. As a (very) general rule, trojan infections is more about data theft and loss of control over the computer; virus infections tend to result in software disruptions or damage.
Trojans may copy and steal your data, but they don’t usually destroy the data file itself; they may stop programs from running but they don’t destroy the program. A virus on the other hand, insert its own code into a program or data file, and depending on how it does so, may either leave the host completely unharmed and functional, slightly disrupted, or completely non-functional.
Another difference between trojans and viruses that really affects the user involves disinfection. For one thing, a trojan is usually a single, discrete program – getting rid of it tends to be fairly simple, a matter of removing the malicious file and its residuals (registry keys, processes, icons, etc). Removing the trojan also generally doesn’t affect the integrity of other files on the computer.
Viruses are far more nebulous by design – they can be present in multiple files, in different locations. Identifying a virus-infected file may require scanning the entire computer to be sure every affected file is caught. Removing malicious code from an infected file or – if it can’t be saved, deleting the infected file entirely – can also be problematic if the damaged data is important or the program is a critical system component.
And this doesn’t even take into account the virus’s payload, which can produce a whole other set of worries.
Still, there is a ray of hope. If current malware trends persist, we may soon see adware or backdoors promoted to being the newest member of The Big Three, and viruses – as a distinct malware type – can finally be relegated to joining 3½” floppy disks in Computer Hell.
In the meantime, here’s some links to other, more in-depth resources on viruses:
Or partially available on Google Books:
Coming soon – Worms!
At Re:publica 2015, our Chief Research Officer Mikko Hypponen told the main stage crowd that the world's top scientists are now focused on the delivery of ads. "I think this is sad," he said. [youtube https://www.youtube.com/watch?v=pbF0sVdOjRw?rel=0&start=762&end=&autoplay=0] To give the audience a sense of how much Twitter knows about its users, he showed them the remarkable targeting the microblogging service offers its advertisers. If you use the site, you may be served promoted tweets based on the following: 1. What breakfast cereal you eat. 2. The alcohol you drink. 3. Your income. 4. If you suffer from allergies. 5. If you're expecting a child. And that's just the beginning. You can be targeted based not only on your recent device purchases but things you may be in the market for like, say, a new house or a new car. You can see all the targeting offered by logging into your Twitter, going to the top right corner of the interface, clicking on your icon and selecting "Twitter Ads". Can Twitter learn all this just based on your tweets and which accounts follow? No, Mikko said. "They buy this information from real world shops, from credit card companies, and from frequent buyer clubs." Twitter then connects this information to you based on... your phone number. And you've agreed to have this happen to you because you read and memorized the nearly 7,000 words in its Terms and Conditions. Because everyone reads the terms and conditions. Full disclosure: We do occasionally promote tweets on Twitter to promote or digital freedom message and tools like Freedome that block ad trackers. It's an effective tool and we find the irony rich. Part of our mission is to make it clear that there's no such thing as "free" on the internet. If you aren't paying a price, you are the product. Aral Balkan compares social networks to a creepy uncle" that pays the bills by listening to as many of your conversations as they can then selling what they've heard to its actual customers. And with the world's top minds dedicated to monetizing your attention, we just think you should be as aware of advertisers as they are as of you. Most of the top URLs in the world are actually trackers that you never access directly. To get a sense of what advertisers learn every time you click check out our new Privacy Checker. Cheers, Jason
F-Secure Labs reported this week on a new WhatsApp scam that’s successfully spammed over 22,000 people. Spam seems to be as old as the Internet itself, and is both a proven nuisance AND a lucrative source of revenue for spammers. Most people don’t see what goes on behind the scenes, but spammers often employ very sophisticated schemes that can expose web surfers to more than just ads for Viagara or other “magic beans”. Spam typically tries to drive Internet traffic by tricking people into clicking certain websites, where scammers can bombard unsuspecting web surfers with various types of advertising. Profit motives are what keep spammers working hard to circumvent spam blocks, white lists, and other protective measures that people use to try and fight back – and it can pay off. Numerous spammers have been indicted and suspected of generating hundreds of thousands of dollars in revenue from their spam campaigns, with one study projecting that spammers could generate in excess of 3.5 million dollars annually. While most spam circulates via e-mail, the popularity of services like WhatsApp is giving spammers new resources to exploit people, and new ways to make money. Here’s a few ways spammers and cyber criminals are using WhatsApp to make money off users: Following Malicious Links: One way that cyber criminals use WhatsApp to scam people is to trick them into following malicious links. For example, a recent scam sent SMS messages to WhatsApp users telling them to follow a link to update the app. But the message was not from WhatsApp, and the link didn’t provide them with any kind of update. It signed them up for an additional service, and added a hefty surcharge to victims' phone bills. Sending Premium Rate Messages: Premium rate SMS sending malware was recently determined by F-Secure Labs to be the fastest growing mobile malware threat, and WhatsApp gives cyber criminals a new way to engage in this malicious behavior. Basically the users receive a message that asks them to send a response – “I’m writing to you from WhatsApp, let me know here if you are getting my messages”, “Get in touch with me about the second job interview”, and various sexual themed messages have all been documented. Responding to these messages automatically redirects your message through a premium rate service. Spanish police claim that one gang they arrested made over 5 million euros using this scheme – leaving everyday mobile phone users to foot the bill. Manipulating Web Traffic: A lot of spam tries to direct web traffic to make money off advertising. As you might imagine, this means they have to get massive numbers of people to look at the ads they’re using for their scams. Scammers use WhatsApp to do this by using the app to spread malware or social engineer large numbers of people to visit a website under false pretenses. F-Secure Labs found that people were being directed to a website for information on where they could get a free tablet. In March there was a global spam campaign claiming people could test the new WhatsApp calling feature. Both cases were textbook scams, and instead of getting new tablets or services, the victims simply wasted their time spreading misleading spam messages and/or exposing themselves to ads. WhatsApp and other services are great for people, but like any new software, requires a bit of understanding to know how to use. Hopefully these points give WhatsApp users a heads up on how they can avoid spam and other digital threats, so they can enjoy using WhatsApp to chat with their friends. [ Image by Julian S. | Flickr ]
Much -- but not all -- of the world celebrates Mothers' Day on the second Sunday of May. If you're celebrating and your procrastinating offspring (or their procrastinating dad) hasn't picked up a present yet, here's a simple -- and FREE -- thing to ask for that will give you peace of mind all year long: online boundaries. We recently released a series of suggestions for age-appropriate digital safety tips for parents that start with a simple truth about kids born in this new millennium: "They switch between devices, applications, and social media throughout the day without even noticing. For them, 'digital life' is just 'life'". If you were born before 1969, you're older than the internet yourself. But your kids are probably younger than the first iPod, which was released in 2001. Advertisers and governments are already tracking their digital footprints, and likely have been for years. And online criminals may be too. You can't prepare your kids for every situation they will face online. You probably can't even imagine every situation they'll eventually face online. But you can save them from numerous difficulties by establishing some basic boundaries. And the younger you begin, the better. Start by setting a reasonable limit for screen time hours that will not overwhelm schoolwork or real life. You can enforce these limits with the help of parental control software. We advise blocking access to social media sites for younger children. If you're going to do this, explain why. This lays the foundation for graduating into approved sites with your permission as they get older. Youthful brain chemistry often prohibits recognizing that time will continue on indefinitely and what you post on the internet will be there forever. Make this clear that what they post could be made public, even if it's in an email, and impossible to delete. And establish how important the privacy of passwords and other identifying data, possibly by using a simile like "Giving that information away is like giving a stranger a key to your life". Tell your child if she or he can agree to one fundamental guideline -- "Tell an adult if something makes you uncomfortable, scared, or confused" -- it will be almost as nice as some new perfume or shoes. Almost. Cheers, Sandra