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June 9th, 2014

Are hackers’ passwords stronger than regular passwords?

Hackers use weak passwords just like the rest of us.

librarian_dict_sm

Nearly two thousand passwords used by hackers were leaked this week, when I tried to decode a PHP shell without knowing the key. Because I did not know the exact content of the encoded file and searching the key could take me years, I chose a different approach. I decided to find out how strong passwords used by hackers are and create a dictionary. :)

Over the years of fighting malware, the avast! Virus Lab has gathered many samples of various back-doors, bots and shells. Some of them are protected with a password encoded in MD5, SHA1 or in plain text, so it was good way to start. I looked at 40,000 samples of hackers’ passwords and found that nearly 2,000 were unique and 1,255 of those were in plain text. Another 346 passwords were easily cracked from MD5 hashes, because they were shorter than 9 characters. That gave me a total of 1,601 passwords and 300 hashes. I created statistics from those words, and here are my findings.

1Passwords that nobody will guess

Percentage of characters used in hackers' passwords

About 10% of the passwords were beyond normal capabilities of guessing or cracking. Of those, I found words as long as 75 characters, probably generated by a computer. Some of them were in long sentence form mixed with special characters such as lol dont try cracking 12 char+. Too bad it was stored in plain text. ;)

There were also passwords that don’t use characters from an English keyboard. But there was still a 90% chance it could be a normal word, maybe with some number in it. No less than 9% of the passwords could be found in an English dictionary.

The table on the right shows which characters are used in hackers’ passwords. The first row means that 58% of passwords contained only lower-case alphabet characters a-z. Read more…

June 5th, 2014

SimpLocker does what its name suggests: Simply locks your phone!

A new Android mobile Trojan called SimpLocker has emerged from a rather shady Russian forum, encrypting files for ransom. AVAST detects the Trojan as Android:Simplocker, avast! Mobile Security and avast! Mobile Premium users can breathe a sigh of relief; we protect from it!

malware, mobile malware, Trojan, SimplockerThe Trojan was discovered on an underground Russian forum by security researchers at ESET. The Trojan is disguised as an app suitable for adults only. Once downloaded, the Trojan scans the device’s SD card for images, documents and videos, encrypting them using Advanced Encryption Standard (AES). The Trojan then displays a message in Russian, warning the victim that their phone has been locked, and accusing the victim of having viewed and downloaded child pornography. The Trojan demands a $21 ransom be paid in Ukrainian currency within 24 hours, claiming it will delete all the files it has encrypted if it does not receive the ransom. Nikolaos Chrysaidos, Android Malware Analyst at AVAST, found that the malware will not delete any of the encrypted files, because it doesn’t have the functionality to do so. Targets cannot escape the message unless they deposit the ransom at a payment kiosk using MoneXy. If the ransom is paid the malware waits for a command from its command and control server (C&C) to decrypt the files.

What can we learn from this?

Although this Trojan only targets a specific region and is not available on the Google Play Store, it should not be taken lightly. This is just the beginning of mobile malware, and is thought to be a proof-of-concept. Mobile ransomware especially is predicted to become more and more popular. Once malware writers have more practice, see that they can get easy money from methods like this, they will become very greedy and sneaky.

We can only speculate about methods they will come up with to eventually get their malicious apps onto official markets, such as Google Play, or even take more advantage of alternative outlets such as mobile browsers and email attachments. It is therefore imperative that people download antivirus protection for their smartphones and tablets. Mobile devices contain massive amounts of valuable data and are therefore a major target. 

Ransomware can be an effective method for criminals to exploit vulnerable mobile users, many of which don’t back up their data. Just as in ransomware targeting PCs, this makes the threat of losing sentimental data, such as photos of family and friends or official documents, immense.

Don’t give cybercriminals a chance. Protect yourself by downloading avast! Mobile Security for FREE.

June 4th, 2014

Black marketed Windows banking & POS Trojan Minerva turns in-the-wild

10309990_1418461665091456_1542203837_oThe path from the creation of malicious program to its delivery onto victims’ computers is long nowadays and involves many different players with the same goal – to make a financial gain. Malware authors usually offer their software to cyber criminals who in turn distribute it via underground forums. This is the how they keep their anonymous status. We have previously seen many famous malicious programs start this way.

In the past, the Russian banking Trojan Carberp was heavily advertised on shady forums. In the beginning of the year, an attempt to sell a new ransomware called Prison Locker was reported. Last year, we blogged about Trojan Solarbot which choose to promote itself through a well- designed website, appearing very official.

However, we don’t always know all the details about every piece of malware, from the code to how it is being distributed. The Trojan dubbed i2Ninja, for example, made headlines last year, but we never received a real sample containing all the functionalities the media reported on. Or do you remember the Hand of Thief Trojan for Linux desktops? Its variant for the Android platform was also advertised, but again, we never encountered it in our Virus Lab. These advertisements could have lacked the real code behind them or may have gone under in the pile of cyberthreats.

In March 2013 a new banking Trojan dubbed Minerva was introduced on a Russian forum. We will see that it is awfully successful in what it promised to do. Read more…

May 29th, 2014

Beware, soccer fans: Not all apps are team players, some shoot for more!

The World Cup in Brazil is just two weeks away, are you in the soccer spirit? The AVAST mobile malware team and I have tournament fever and have been downloading games and other soccer related apps from the Google Play store. We unfortunately noticed that some of the fun apps we downloaded weren’t as entertaining as we thought they would be…

AVAST detects fake soccer gaming app: Android:FakeViSport

Some of the Android gaming apps we downloaded primarily displayed ads instead of letting us play. Let me just point out a few from many. We were unable to play Corner Kick World Cup 2014 at all because it displayed nothing but a white screen, with ads popping up now and then. This app struck me as odd from the get go. When I checked the size of the app I noticed it was really tiny, less than 1MB. What kind of game can you expect from an app this size?! What is even more interesting is that the game is made by a developer called VinoSports. If you check the rest of his apps offered on Google Play they are all the same – just blank applications stuffed with advertisements.

Vinospots

wideThis is unfortunately a quite common and sneaky way for developers to make some money. With applications like this, the only person who benefits from them are the developers. They may get some money if you actually click on the ads their apps display. We decided to block apps from VinoSports. From now on, they will be detected as Android:FakeViSport. They are fake applications in that they pretend to be something desirable, but they aren’t.

Some apps are in the gray zone

The second app I would like to mention is Fifa 2014 Free – World Cup. The app comes from a pretty big developer, “Top Game Kingdom LLC”, who has plenty of apps on Google Play and other stores. This however does not mean the app should be trusted. Fifa 2014 Free – World Cup, can be considered, at the very least, suspicious.

As for the app Football World Cup 14: The application’s installation package name doesn’t have anything to do with the name of the app itself. The app is called Football World Cup 14, yet its installation package is called “com.topgame.widereceiverfree”.Football World Cup 14, also known as “Widereceiverfree” requests access to information that has nothing to do with the app’s function, like location, call log, and to other accounts on the phone.

Weirdly enough the Football World Cup 14′s developer has even more applications on the market, most of them behave similarly. They pretend to be something different than what they really are. In the end you might get something that can be considered a game, a game with plenty of obstacles such as and with permissions that could easily misuse personal information.

Tom game kingdom

Apps that display ads are not necessarily malicious. Plenty of apps, especially free apps, are funded by ads. They can, however, be annoying, particularly when they don’t go away and prevent you from using the app itself. Apps that access more information from your phone than they need to function seem harmless, especially since there is no visible evidence of this happening, but they can cause more harm than you may think.

We recommend you to take a closer look at the apps you download during tournament time, be it gaming apps, live streaming apps or apps that allow you to bet for your national team, to make sure you stay safe and as ad free as possible!

Things to look out for when downloading apps:

  1. Make sure you download from official apps markets. Many of our mobile malware samples come from unofficial app markets, only very few come from the official Google Play store.
  2. Download official apps you can trust. Google Play is an open and developer friendly platform, which is why it contains a plethora of apps. We totally understand why people are sometimes overwhelmed with all the apps they can choose from, we found over 125 vuvuzela apps on Play! We recommend users play it safe and download official apps from developers they can trust. Trusted developers appreciate their users, meaning they want to provide them with a quality product, not one that is flooded with apps. FIFA has a great live score/news appand EA Sports has an official FIFA gaming app.
  3. Compare app functionalities to the access they request. Some apps need access to certain data on your device, a map app needs access to your location so it can give you directions. App access requests start becoming suspicious when for example your vuvuzela app wants access to your location. Unless your new vuvuzela app uses your location to determine what country you are in to then play your country’s national anthem, why does it need to know your location? Always be cautious when giving apps access and make sure the requests make sense depending on what the app does. You don’t want to carelessly hand over sensitive information that could later be used against you.
  4. Read user comments. You can’t always trust what people write online, but if multiple people really appreciate or dislike an app you can get a good idea of whether or not you should download it based on the feedback they give.

Our mobile security app avast! Mobile Premium has an Ad Detector feature. Ad Detector finds out which apps are linked to ad networks and provides details of their tracking system, so you have a full overview of all the ad networks contained within your apps.

You can download avast! Mobile Security for free from Google Play or for additional features, like Ad Detector, you can download avast! Mobile Premium for $1.99 a month.

 

 

May 12th, 2014

Browser Ransomware Attacks are Massive in Scale

avast! Virus Lab infographic shows how prolific and wide-spread Browser Ransomware attacks have been over the last three months.

AttentionLeaving page alert

During December I wrote about the tricks and tactics of Browser Ransomware. Browser Ransomware is malware that works in different types of browsers to prevent people from using their PCs. To get access back to their own PC, the victim of this malware must pay a ransom to unblock it. The key to success for this attack is its translations into many different languages, giving the cybercrooks a bigger pool of potential victims.

Today I would like to look back on Browser Ransomware attacks and share some data from our avast! CommunityIQ with you.

We detect Ransomware attacks using several different methods.  The detections I checked were created January 30, 2014. I was really surprised at the huge impact this attack has had on AVAST users.

  • In a little under 3 months, AVAST protected more than a half million unique users around the world from Ransomware attacks.
  • In the past 6 weeks, AVAST users have unknowingly visited a site with Ransomware on it over 18 million times.
  • During last 24 hours, AVAST stopped redirection from infected sites to sites hosting Ransomware for more than 18,000 unique users. Read more…
May 7th, 2014

Fake government ransomware holding Android devices hostage

Ransomware, which has already made its rounds on Windows, is now increasingly targeting the Android operating system. A new piece of mobile malware claiming to be the government under the name Android: Koler-A is now targeting users.

We have full control of your phone – give us $300 and we’ll give it back

Obrázek 1-1

The ransomware is pushed automatically from fake porn sites visited by Android users via a malicious .apk file that appears in the form of an app. The innocent appearance of the app deceives users and is a powerful social engineering tactic used by malware developers to trick people into installing malicious apps. The form of delivery is not the only thing that makes the app suspicious and potentially dangerous, but the access it seeks are highly unusual and alarming. The ransomware requests full network access, permission to run at startup and permission to prevent the phone from sleeping. Once installed the granted access allows the ransomware to take control of the device. The full network access allows the malicious app to communicate over the web and download the ransom message that is shown on the captive device. The permission to run at startup and prevent the phone from sleeping fully lockdown the phone, preventing victims from escaping the ransom message.

The ransomware localizes fake government messages, depending on the users GPS location, accusing them of having viewed and downloaded inappropriate and illegal content. What does the ransomware do next? Demands ransom of course! The ransom to regain access to the device including all of its apps, which it claims are all encrypted, is set at around $300 and is to be paid through untraceable forms of payment such as MoneyPak.

avast! Mobile Security safeguards against ransomware

Both AVAST’s free and premium mobile security apps, avast! Mobile Security and avast! Mobile Premium, protect customers from falling for the devious apps containing ransomware. AVAST detects this ransomware under the name Android: Koler-A and blocks its execution.

We recommend that everyone be cautious when downloading apps, especially from unofficial app markets. We also urge users to not open any files that have been downloaded to their device without their consent. Always check what apps want to access and in addition to being cautious, we advise people download antivirus to protect their devices. This new ransomware appearing on Android is the perfect example of how malware is starting to move away from the PC environment and into our pockets and there are no signs of this slowing down.

Thank you for using avast! Antivirus and recommending us to your friends and family. For all the latest news and product information, please follow us on Facebook, Twitter, Google+ and Instagram. Business owners – check out our business products.

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April 17th, 2014

WordPress plugin vulnerability puts mobile visitors at risk

AVAST finds WordPress plugin redirector

AVAST finds new twist on WordPress plugin vulnerability

Today one of our colleagues came into our office and said, “Hey guys, I’ve been infected.” I thought to myself, yeah, how bad can this be? After a bit of digging we found the results were worth it; it turned out to be a really “interesting ” case of mobile redirected threats localized for each country.

All you need is one bad IP

The case was brought to us by Jakub Carda, a fellow AVAST employee who enjoys blogging in his free time. His WordPress site was compromised through a vulnerability in WordPress, more precisely OptimizePress. OptimizePress is a WordPress plugin that fully integrates itself into the WordPress CMS, helping bloggers optimize their blog’s design. A tiny mistake in the code of a file located in: lib/admin/media-upload.php made it possible for pretty much anyone to upload harmful content onto people’s WordPress sites, and plenty of websites have been compromised because of this.

Read more…

April 10th, 2014

Behind the CARO conference’s curtains: Meet AVAST speakers!

For seven years, the CARO Workshop has been hosted in Europe. It is an outstanding technical meeting, attended by some of the best malware researchers in the world. In 2014, the CARO workshop comes to America. ~CARO’s conference official website

We are proud and happy to introduce you to our AVAST speakers and Security Experts from the Virus Lab. Peter Kálnai and Filip Chytrý are going to CARO’s (Computer Antivirus Research Organization) workshop to“Declare war against Android Malware.” We sat together and talked about their presentation, mobile malware, and general trends in the security industry.

Meet our security experts: Peter and Filip.

 

The theme for this year’s CARO conference is Mobile Space: Malware in a mobile world. As security experts, what changes and specific trends in malware development have you observed?

FILIP Well, this may sound cliché,  but the amount of mobile threats are rising and more sophisticated attacks appear every day. A few years ago, we would observe mostly primitive malware with only one or two capabilities such as to send paid SMS or track your movements. Now, however we have malware that can root your phone and became a device administrator, or command and control Apps which take control of your device by attackers. That’s why I believe we can stay tuned for more conferences concentrated on Android malware.  CARO is first, but hopefully not the last, conference focused on Android and mobile threats.

PETER I can’t recollect a different example, but this year’s CARO Workshop seems to be the first IT security conference completely devoted to mobile malware. The topic of our talk reflects trends in the Android threat landscape. Security experts nowadays observe an increased ratio of total malicious Android packages to unique malware families. Two particular cases appear most: The expansion of usage of Android packers and repackaging benign application with malicious code, so called piggybacking. Read more…

April 2nd, 2014

Declaring machine war against malicious Android packages

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Do you know the notion “machine war”? If you’re a fan of the Matrix movie trilogy then probably, yes. It denotes the fictional rise of artificially intelligent machines against the human race and their violent conquest of human beings. We want to apply a similar dominance of computationally powerful machines, not to create a population of slaves, but against numerous malicious Android packages that wildly proliferate on unofficial markets.

The idea of malware detection with no human interaction appeared earlier on our blog. In a fundamental article about AVAST research activities by AVAST’s COO, Ondřej Vlček, he effectively described the technologies we employ to deal with Windows threats. Two techniques have been mentioned explicitly, Malware Similarity Search and Evo-Gen, both working with Windows PE file format. Sometimes the latter form of detection technique is denoted as weak automated anti-malware heuristic.

The main effort is to reach two slightly conflicting qualities at the same time: The robustness, which means that suggested methods cover as many threats as possible; and simplicity, so that the methods are easily implemented in AVAST’s mobile security solution. The search for balance between those qualities is assisted by lessons learned from automated heuristic for Windows PE executables.

Read more…

April 1st, 2014

Email with subject “FW:Bank docs” leads to information theft

In this blogpost we will look deep into a spam campaign, where unlike other possible scenarios, the victim is infected by opening and running an email attachment. In the beginning of this year, we blogged about a spam campaign with a different spam message – a fake email from the popular WhatsApp messenger. This time we will look at spam email which tries to convince the victim that it originates from his bank. The malicious email contains contents similar to the following one:


Subject: FW: Bank docs

We have received this documents from your bank, please review attached documents.
<name, address>

 

promo Read more…

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