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Posts Tagged ‘ransomware’
September 2nd, 2015

Apple jailbroken phones hit with malware

Chinese jailbroken iPhone users targeted

Chinese jailbroken iPhone users targeted

“Biggest iPhone hack ever” attacks jailbroken phones

In what has been called the biggest iPhone hack ever, 250,000 Apple accounts were hijacked. That’s the bad news.

The good news is that most Apple device users are safe. Why? Because the malware dubbed KeyRaider by researchers at Palo Alto Networks, only infects “jailbroken” iOS devices. (there’s that bad news again)

When you jailbreak a device like an iPhone or iPad, it unlocks the device so you can do more with it like customize the look and ringtones, install apps the Apple normally would not allow, and even switch carriers!

The KeyRaider malware entered the jailbroken iPhones and iPads via Cydia, a compatible but unauthorized app store, which allows people to download apps that  didn’t meet Apple’s content guidelines onto their devices. The malware intercepts iTunes traffic on the device to steal data like Apple passwords, usernames, and device GUID (“Globally Unique Identifier” which is your ID number similar to your car’s VIN). Users reported that hackers used their stolen Apple accounts to download applications from the official App Store and make in-app purchases without paying. At least one incident of ransomware was reported.

Chinese iPhone users with jailbroken phones where the primary attack target, but researchers also found incidents in 17 other countries including the United States, France, and Russia.

Read more…

August 20th, 2015

Mr. Robot Review: m1rr0ring.qt

This week’s episode of Mr. Robot continued from where it left off last week, focusing on the show’s characters rather than hacking methods. We see Elliot struggle with himself as he figures out that Mr. Robot is his dad (who died years ago), who he has been imagining in his mind. Meanwhile, Tyrell’s world is crumbling. His wife gave birth to a baby boy, but tells him she does not want to be with him unless he “fixes things”. He then gets fired from E Corp and remains as the prime suspect in Sharon’s murder investigation. It doesn’t look like Tyrell did a very good job of fixing things, if you ask me…

Despite the lack of hacking, I did have a few questions about the final scene of the episode. I spoke with my colleague, senior malware analyst Jaromir Horejsi, who helped me better understand FSociety’s plan.

via: USA Networks - Mr. Robot airs on USA, Wednesdays at 10/9 central

In the last scene of the episode, Tyrell pays Elliot a visit. Tyrell tells Elliot about how he murdered Sharon and how surprisingly good that felt. Elliot then decides to tell Tyrell about his plan to take down E Corp. Elliot explains to him that by encrypting all of E Corp’s files, all of their financial records will be impossible to access as the encryption key will self-delete after the process completes.

Read more…

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August 20th, 2015

Infected ad networks hit popular websites

Infected ads can be dangerous to your computerIt is frustrating when your antivirus protection stops you from visiting a website that you know and trust, but these days even the most popular websites can fall prey to attacks.

This week security researchers discovered booby-trapped advertisements on popular websites including eBay, The Drudge Report, weather.com, and AOL. The ads, some of which can be initiated by a drive-by attack without the user’s knowledge or even any action, infected computers with adware or locked them down with ransomware.

Computer users running older browsers or unpatched software are more likely to get infected with malware just by visiting a website. Avast blocks these infected ads, but to be safe, please use the most updated version. To update your Avast, right-click the Avast Antivirus icon in the systems tray at the bottom-right corner of your desktop. From the menu, select Update.

“This kind of malvertising is a fairly easy way for cybercriminals to deliver adware or another malicious payload. Many websites sell advertising space to ad networks then deliver the targeted ads to your screen,” said Avast Virus Lab researcher Honza Zika. “All Avast users with current virus databases are fully protected against this attack, but those without protection or up-to-date security patches run the risk of being infected with ransomware.”

Read more…

July 15th, 2015

One in 10 American mobile users is the target of mobile malware

Avast Antivirus detects and neutralizes malware

Threat analysts and malware researchers in the Avast Virus Lab detect and neutralize threats as soon as they appear.

The Avast Threat Report provides an overview of global threat activity.

 

Avast malware researchers and Avast customers work 24/7 to protect each other.

Avast protects 230 million people worldwide in more than 186 different countries — we are present in more countries than McDonalds and protect more people than any other antivirus security provider. We stream 250 micro updates a day that protect our users from attacks. This is made possible by the 230 million devices we protect that simultaneously act as de facto sensors. These sensors provide us with information about suspicious files to help detect and neutralize threats as soon as they appear. Once we identify a suspicious file on a single device, it is reported back to the Avast servers and all Avast users around the world are immediately protected. This is called our Community IQ – it not only lets us better protect our users but also gives us valuable insights into the current security landscape.

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July 3rd, 2015

CryptoWall joins forces with click fraud botnet to infect individuals and businesses alike

Newest CryptoWall variant enters systems through a click fraud botnet.

Newest CryptoWall variant enters systems through a click fraud botnet.

Earlier this year, we told you about the return of CryptoWall, malware that encrypts certain files in your computer and, once activated, demands a fine around $500 as a ransom to provide the decryption key. These kinds of financial fraud schemes target both individuals and businesses, are usually very successful and have a significant impact on victims. The problem begins when the victim clicks on an infected advertisement, email, or attachment, or visits an infected website.

Recently, a click fraud botnet with ties to CryptoWall has been discovered. The malware, nicknamed ‘RuthlessTreeMafia‘, has been being used to distribute CryptoWall ransomware. What first appears as an attempt to redirect user traffic to a search engine quickly mutates into an alarming threat as infected systems begin to download CryptoWall and system files and data become encrypted, rendering them useless by their owners. Click fraud and ransomware are two types of crimeware that are usually quite different from one another and typically don’t have many opportunities to join forces; therefore, the result of this unlikely yet powerful collaboration can be detrimental to its victims.

Read more…

April 7th, 2015

Don’t take the bait: Beware of web attack techniques

Mousetrap with cheese

When it comes to cybercrime, it’s always better to be in the know. Here are a few ways that web attacks can find their way onto your device. Don’t be fooled — most cybercrooks design attacks to  take place where you’d least expect it.

  1. Social engineering preys on human weakness

“A lot of attacks are still using social engineering techniques; phishing emails – ways of convincing the user to give up valuable information,” said Avast CEO Vince Steckler.

In a phishing or spearphishing attack, hackers use email messages to trick people into providing sensitive information, click on links, or download malware. The emails are seemingly sent from organizations or individuals the potential victims would normally get emails from, making them even more deceptive. Last July, Avast took a look at the Tinba Trojan, banking malware that used spearphishing to target its victims.

 usbank

An example of an injected form from Tinba Trojan targeting U.S. Bank customers.

Web attacks also take place through SMS Text Phishing, also known as SMSishing. This method has become one of the most popular ways in which malicious threats are transmitted on Android devices. These text messages include links that contain malware, and upon clicking them, the malicious program is downloaded to the user’s device. These programs often operate as SMS worms capable of sending messages, removing apps and files, and stealing confidential information from the user.

  1. Malicious apps attempt to fool you

Malicious programs can disguise themselves as real programs by hiding within popular apps or games. In February, we examined malicious apps posing as games on Google Play that infected millions of users with adware. In the case of malicious apps, cybercrooks tamper with the app’s code, inserting additional features and malicious programs that infect devices. As a result, the malware can attempt to use SMSishing in order to collect additional data.

Durak-game-GP

The Durak card game app was the most widespread of the malicious apps with 5 – 10 million installations according to Google Play.

  1. Ransomware uses scare tactics that really work

Another name that made headlines was a group of malware dubbed ransomware, such as CryptoLocker, and its variants CryptowallPrison LockerPowerLocker, and Zerolocker. The most widespread is Cryptolocker, which encrypts data on a computer and demands money from the victim in order to provide the decryption key. Avast detects and protects its users from CryptoLocker and GameoverZeus.  

Make sure you back up important files on a regular basis to avoid losing them to ransomware. Ransomware made its way from desktop to Android during the year, and Avast created a Ransomware Removal app to eliminate Android ransomware and unlocks encrypted files for free.

Count on Avast apps to keep mobile malware at bay

To keep your devices protected from other ransomware, make sure to also install Avast Free Mobile Security & Antivirus from the Google Play store. It can detect and remove the malware before it is deployed.

Install Avast Ransomware Removal to find out if your Android devices are infected and to get rid of an infection. Avast Ransomware Removal will tell you if your phone has ransomware on it. If you are infected, it will eliminate the malware. Android users who are clean can use the free app to prevent an infection from happening.Once installed, you can easily launch the app to scan the device, remove the virus, and then decrypt your hijacked files.

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March 17th, 2015

Ransomware holds eSports players hostage

Dreaded ransomware, the malware that locks your files and demands payment for the key to unlock them, is now targeting gamers.

New ransomware targets gamers.

 

In the first report of gamers being targeted by ransomware, more than 2o different games, including World of Warcraft, League of Legends, Call of Duty and Star Craft 2, various EA Sports and Valve games, and Steam gaming software are are on the list.  This variant of ransomware looks similar to CryptoLocker according to a report from a researcher at Bromium Labs.

What is CryptoLocker?

CryptoLocker is “ransomware” malware that encrypts files on a victim’s Windows-based PC. This includes pictures, movie and music files, documents, and certain files, like the gamer’s data files, on local or networked storage media.

A ransom, usually paid via Bitcoin or MoneyPak, is demanded as payment to receive a key that unlocks  the encrypted files. In previous cases, the victim has 72 hours to pay about a relatively small amount of money, usually in the low hundreds of dollars, but after that the ransom rises to over thousands of dollars. We have seen reports that says the gamers are demanded a ransom of about $1,000 via PayPal My Cash Cards or 1.5 bitcoins worth about $430.

“There’s mostly no way to get the data back without paying the ransom and that’s the reason why bad guys focus on this scheme as it generates huge profit, “ said  Jiri Sejtko, Director of Avast Software’s Virus Lab Operations last year when ransomware was making the news. “We can expect some rise in ransomware occurrences,” predicted Sejtko. “Malware authors will probably focus on screen-lockers, file-lockers and even on browser-lockers to gain money from victims.”

That prediction came true, and now ransomware authors are targeting narrower audiences.

How do I get infected with CryptoLocker?

Infection could reach you in various ways. The most common is a phishing attack, but it also comes in email attachments and PDF files. In the new case targeting gamers, the Bromium researcher wrote, “This crypto-ransomware variant has been getting distributed from a compromised web site that was redirecting the visitors to the Angler exploit kit by using a Flash clip.” There is a detailed analysis in the report.

Read more…

February 10th, 2015

Mobile Crypto-Ransomware Simplocker now on Steroids

In June 2014, we told you about mobile ransomware called Simplocker that actually encrypted files (before Simplocker, mobile ransomware only claimed to encrypt files to scare users into paying). Simplocker infected more than 20,000 unique users, locking Android devices and encrypting files located in the external storage. Then, it asked victims to pay a ransom in order to “free” the hijacked device. It was easy to decrypt the files affected by this variant of Simplocker, because the decryption key was hardcoded inside the malware and was not unique for each affected device.

Dangerous unique keys

keyBut now there is a new, more sophisticated variant of Simplocker in town that has already infected more than 5,000 unique users within days of being discovered. The reason why this variant is more dangerous than its predecessor is that it generates unique keys for each infected device, making it harder to decrypt infected devices.

To use an analogy, the original variant of Simplocker used a “master key” to lock devices, which made it possible for us to provide a “copy of the master key” (in the form of an app, Avast Ransomware Removal) to unlock already infected devices. The new variant however, locks each device with a “different key” which makes it impossible to provide a solution that can unlock each infected device, because that would require us to “make copies” of all the different “keys”.

Why would anybody install Simplocker?!

The reason why people install this new variant of Simplocker is because it goes undercover, meaning people don’t even realize that what they are installing is ransomware!

Fake Flash

Tricky Simplocker pretends to be a real app.

 

In this case, the new variant of Simplocker uses the alias “Flash Player” and hides in malicious ads that are hosted on shady sites. These ads mostly “alert” users that they need Flash Player installed in order to watch videos. When the ad is clicked on, the malicious app gets downloaded, notifying the user to install the alleged Flash Player app. Android, by default, blocks apps from unofficial markets from being installed, which is why users are notified that the install is being blocked for security reasons.
Device Admin Request

 

Users should listen to Android’s advice. However, users can go into their settings to deactivate the block and download apps from unknown sources. Once installed, a “Flash Player” app icon appears on the device and when it is opened the “Flash Player” requests the user grant it administrator rights, which is when the trouble really begins.

As soon as the app is granted administrator rights, the malware uses social engineering to deceive the user into paying ransom to unlock the device and decrypt the files it encrypted. The app claims to be the FBI, warning the user that they have found suspicious files, violating copyright laws demanding the user pay a $200 fine to decrypt their files.

device-2015-02-05-143216  FBI warning is an example of social engineering

What should I do if I have been infected?

We do NOT recommend you pay the ransom. Giving into these tactics makes malware authors believe they are succeeding and encourages them to continue.

If you have been infected by this new strain of Simplocker, back up the encrypted files by connecting your smartphone to your computer. This will not harm your computer, but you may have to wait until a solution to decrypt these files has been found. Then boot your phone into safe mode, go into the administrator settings and remove the malicious app and uninstall the app from the application manager.

Avast protects users against Simplocker

Avast Mobile Security protects users against both the old and new variant of Simplocker, the new variant is detected as: Android:Simplocker-AA.

A more technical look under the hood:

As the fake FBI warning is being shown to users, the malware continues working in the background, doing the following: Read more…

January 19th, 2015

An old threat is back: Ramsonware CryptoWall 3.0. Get Avast for protection.

The nightmare is back! Your security could be seriously compromised if you do not act now. Install and update your Avast for PC before is too late. The original version of CryptoWall was discovered in November 2013, but a new and improved variant of the CryptoWall ransomware starts to infect computers all over the world last days. It’s the CryptoWall 3.0. Some sources estimate that it has already infected over 700,000 computers up to version 2.0.

Avast detects and blocks ransomware

Avast Software Updater can help identify software that needs to be updated.

CryptoWall is a malware that encrypts certain files in your computer (and secure delete the original ones) and, once activated, demands a fine around $500 as a ransom to provide the decryption key. You’re asked to pay in digital Bitcoins in about 170 hours (almost a full week). After that period, the fee is raised to $1000.

You could be asking why haven’t the authorities blocked the financial funding of them? They use unique wallet ID for each victim into their own TOR anonymity servers. For the user to be able to pay the ransom, he needs to use a TOR-like connection called Web-to-TOR. Each TOR gateway redirects the victim to the same web page with the payment instructions. The commands and communication control is now done using Invisible Internet Project (I2P) instead of Tor.

Infection could reach you in various ways. The most common is as a phishing attack, but it also comes in email attachments and PDF files. The malware kit also abuses various vulnerabilities in unpatched – read non up-to-date – Flash, Java, browsers and other applications to drop the CryptoWall ransomware.

How Avast prevents the infection

1. Avast Antispam and antiphishing protection prevents some vectors distribution.

2. Virus signature block all known ransomwares versions. Remember that Avast automatic streaming updates releases hundreds of daily updates for virus definitions.

3. Community IQ intelligence and sensors of our more than 220 million users that detects malware behavior all over the world. See how it works in this YouTube video.

4. Keeping your software updated is another security measure that prevents the exploit of their vulnerabilities. Learn how Avast Software Updater can help you with this job.

What more can I do?

Avast also helps in prevention of this disaster through its Avast Backup that allows you to keep all your important files in a secure and encrypted way. We also recommend local backup, as the new malware could also attack other drives and even cloud storage. Did you know that Avast Backup also performs local copies of the files? You can enable it at Settings > Options > Local backup, and configure the backup location (better an external drive) and also versioning of the files. Remember to disconnect the external drive from the computer (and the network) to prevent infection of the backups by CryptoWall and further encryption of the files.

Avast Software’s security applications for PC, Mac, and Android are trusted by more than 200-million people and businesses. Please follow us on Facebook, Twitter and Google+.

August 27th, 2014

Self-propagating ransomware written in Windows batch hits Russian-speaking countries

Ransomware steals email addresses and passwords; spreads to contacts.

Recently a lot of users in Russian-speaking countries received emails similar to the message below. It says that some changes in an “agreement’ were made and the victim needs to check them before signing the document.

msg
The message has a zip file in an attachment, which contains a downloader in Javascript. The attachment contains a simple downloader which downloads several files to %TEMP% and executes one of them.
payload
The files have .btc attachment, but they are regular executable files.

coherence.btc is GetMail v1.33
spoolsv.btc is Blat v3.2.1
lsass.btc is Email Extractor v1.21
null.btc is gpg executable
day.btc is iconv.dll, library necessary for running gpg executable
tobi.btc is   Browser Password Dump v2.5
sad.btc is sdelete from Sysinternals
paybtc.bat is a long Windows batch file which starts the malicious process itself and its replication

After downloading all the available tools, it opens a document with the supposed document to review and sign. However, the document contains nonsense characters and a message in English which says, “THIS DOCUMENT WAS CREATED IN NEWER VERSION OF MICROSOFT WORD”.

msg2 Read more…