A quick guide to mobile malware (part 2)

This is the second article in a 3-part series on mobile malware.

Why (should I be worried)?

Worm:iOS/Ikee.A changed the phone's wallpaper

Last week I gave a brief summary of the kinds of threats a user might encounter on the smartphones of today. This week’s article is supposed to cover the reasons why a user would worry about mobile malware, so let me give the short answer now:

Usually, mobile malware attacks are motivated by: Bragging rights; money; stealing personal information that can be sold for money. For the user that gets hit by the malware, it means: Losing control over your phone; losing your money; someone else might be using your personal details for who-knows-what.

So let’s assume your phone’s been infected. Just how much should you be worried? Well, that kind of depends on your luck and what kind of malware you’re dealing with.

“Hey folks! Look what I can do!”

Like PC-based malware, the first threats to appear on the phone are often the product of some technically-minded person finding a loophole in the phone’s operating system, writing a program to exploit it, then releasing it to the general public to, basically, prove that it can be done. A prank for bragging rights, more or less. There may also be more subtle motivations involved, but if your phone is on the receiving end, you probably wouldn’t care.

Sometimes, if you’re lucky, that first malicious program doesn’t do anything worse than changing the phone’s wallpaper (Worm:iOS/Ikee.A is a good example here). So, for the user, the cost for the malware creator’s bragging rights is: time spent dealing with the problem and probably a massive headache.

Not a good loss, but bearable. Unfortunately, the next two potential losses for a user hit by mobile malware – money and/or personal data – are more serious.

“Give me back my phone!”

As other attackers get hold of that pioneer program and modify it to be more malicious, the next few versions (or variants) of it usually get more ‘risky’ to the user. If the malware is really malicious, it can alter the phone’s functionality to the point that the device is basically ‘bricked’ – it can’t be used for anything other than a paperweight.

Some examples we saw on the Symbian platform – which, by virtue of being the first widely used smartphone platform, also suffered the most threats – were Cardtrap, Skulls, Romride and Locknut. At this point, if the damage isn’t recoverable, the user is also out by the price of the phone and loss of the data stored on the phone itself. Ouch.

SMSes = $$$

Still, not everyone has to be concerned about data loss, if they have their contacts backed up elsewhere and they don’t keep financial or confidential details on their phone. What if you do, though? Say, you do mobile bank transactions, or store your PINs or account log-in details on the phone? Can an attacker find a way to pull confidential data off the phone?

‘Early generation’ smartphones – for the sake of this article, let’s say they’re the ones that sent data out by WAP  – didn’t give crooks a lot of options for getting hold of data they could make money from.  On these phones, the ‘traditional’ way for crooks to make money was through what amounts to SMS fraud (an example is the Redoc trojan family).

In this kind of scheme, the attackers has to plant a trojan on the device that forces it to send SMS messages to a premium phone number, which can wrack up a high phone bill for the user. Though effective, these attacks tend not to be very widespread, as they are limited by the geographical location and size of the telecom networks and target-able users. If you’re not in the target group, the threat is almost nonexistent.

Stealing data

Nowadays though, ‘new generation’ smartphones – as in ones with fast data connections back up by unlimited or cheap data packages from telco providers, making it convenient for a user to just leave the data connection open – offer a crook more options. Instead of bothering with SMS fraud, they can create malware that find and retrieve specific information stored on the device, which could potentially give far greater returns. Case in point is the very next Ikee variant, Ikee.B, which stole financially-sensitive information stored on the phone.

In this case, the loss is hard to estimate as fortunately, this type of malware isn’t common and the risk they pose is highly individual, depending on what details you store on your phone. It would probably also depend on how the attacker would be able to convert the details stolen into hard cash – sell it off in bulk together with details stolen from others? Find a way to log into a compromised account and withdraw the money?

There’s no ‘standard scenario’ here, so it’s hard for a user to realistically evaluate the fallout of having data stolen off their phone. All that can be reliably said is that personal and financial details are major targets on a PC and they’re probably no less attractive on mobile devices; it’s just that up until now, attackers didn’t have a way to scam these details out of someone on a mobile device.

Going straight for the money

As with PC threats, the main motivation for mobile threats seems to have transitioned from bragging rights to making money. And in a totally unscientific personal observation, it sure seems like mobile malware made that transition much faster than PC threats did. As a very rough comparison:

  • Brain, the first PC-based malware, came out in 1986; it was only in the early 2000’s that profit-motivated malwares became prevalent (though there doesn’t seem to be any agreement on which was the first).
  • By comparison, the iOS was launched in early 2007; its first trojan (of the bragging rights variety) came out almost exactly a year later; and shortly thereafter came Ikee.B, which was more malicious (but only on jailbroken iPhones).
  • The Android OS was launched in late 2007; its first trojan was also the first to try an SMS fraud scam, and it appeared in August of 2010.

It’s early days yet for mobile threats so we really don’t know how they are going to evolve.

It would probably be a safe bet to say that there are going to be more new threats though, and not all of them are going to be as benign as a plastering on a Rick Astley wallpaper.

Next week, the last in this series – How (can I protect myself)?

More posts from this topic


Cyber Monday Mythbusting

It's Cyber Monday, and marketing companies expect online shoppers to flock to websites and apps in order to take advantage of holiday sales. And naturally, this causes concerns about what kind of risks people are taking when they shop online. But F-Secure Security Advisor Sean Sullivan says any security warnings focusing on Cyber Monday are simply part of the hype. “Cyber Monday is no more or less safe than any other day of the year. People just expose themselves to more online threats when they do more stuff online, but that really has nothing to do with Cyber Monday. And people that tell you otherwise aren’t doing you any favors.” So there you have it. On the other hand, Sullivan does point out that holiday shoppers should beware of the extent to which they expose themselves while online shopping, which is becoming more popular during the holidays. Adobe is projecting an eleven percent increase in online spending during the holidays this year, amounting to a whopping 83 billion dollars. So that’s 83 billion dollars that will be up for grabs (compared to just 3 billion on Cyber Monday), so it’s naïve to think that criminals are just going to ignore the opportunity. Last year, F-Secure Labs registered a sharp increase in ransomware detections during November and December, including a 300 percent increase in the Browlock police-themed ransomware family. Sullivan published a recent blog post examining the Crytowall ransomware family, which he says is prevalent during the holiday season but virtually disappears in early January – when people celebrating Orthodox Christmas in Russia begin their holidays. One easy way to protect yourself from ransomware and other online threats while holiday shopping is to be conscious of the threat landscape. Its trends like these that Sullivan pays attention to, and warns others to do the same. “It would be safe to say that people should be worried about ransomware this holiday season, and probably through next year. I expect that we, or at least security researchers, will look back on 2016 as the year of extortion.” For example, even though mobile device are now widespread and used by many people, they’re not necessarily good tools to use for making financial transactions while online shopping. “I use an iPad running Freedome for the vast majority of my online browsing, which works great for me because it’s easy to use and I can bring it with me if I leave the house. And between the security benefits of a VPN and the relatively small amount of malware targeting iOS devices, I feel pretty confident in using it to casually window shop on different websites. But I always use a PC to make actual purchases. I trust that my PC is secure and the actual keyboard makes it easier to enter financial data.” You can find more great advice on how to stay safe while online shopping here. [Image by Atomic Taco | Flickr]

November 30, 2015

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