Locky Ransomware

Locky is now one of the most commonly seen types of ransomware

Jeremy Kirk
IDG News Service Mar 10, 2016 3:50 AM

Locky, a new family of ransomware that emerged in the last few weeks, has quickly made a mark for itself.

Computer security companies say it has become a commonly seen type of ransomware, which is used to hold a computer’s files hostage pending a ransom payment.

Trustwave’s SpiderLabs said on Wednesday that 18 percent of 4 million spam messages it collected in the last week were ransomware-related, including many linked to Locky.

“We are currently seeing extraordinary huge volumes of JavaScript attachments being spammed out, which, if clicked on by users, lead to the download of a ransomware,” wrote Rodel Mendrez, a Trustwave security researcher.

Locky is distributed through spam messages that have been sent through the same botnet used to send Dridex, the infamous online banking malware.

At first, the spam messages contained malicious Microsoft Word documents with macros that would download Locky. But McAfee wrote on Monday that recent Locky spam contains an obfuscated JavaScript file, which if executed downloads the ransomware.

“We believe the change to JavaScript is to evade antimalware products due to its obfuscation and small size, which suggests the file is benign,” McAfee wrote.

Security vendor Fortinet studied statistics collected by its Intrusion Prevention System software between Feb. 17 and March 2. The software detects when ransomware connects to command-and-control servers used by cybercriminals to manage the malware.

It found that about 16.4 percent of 18 million communications it detected were for Locky infections, with the rest belonging to CryptoWall and TeslaCrypt, the other top ransomware families.

“As predicted, Locky already covers a big chunk of the infections,” wrote Roland Dela Paz, senior antivirus analyst with Fortinet.

Most of the Locky infections appear to be in the U.S., France and Japan, he wrote.

The FBI has warned that ransomware has become one of the biggest threats to consumers and businesses. Although some ransomware writers made mistakes in their code early on, there’s usually no way to recover the files if the decryption key is not released.

The ransom is usually a few hundred dollars, with detailed instructions displayed to victims for how to pay in bitcoin. Security experts generally recommend backing up files to recover from a ransomware attack and ensuring the backup drive can’t be reached by malware.

Jigsaw Ransomware

Locky is now one of the most commonly seen types of ransomware

Lawrence Abrams
Bleeping Computer April 11, 2016 5:20 pm

A new ransomware has been released that not only encrypts your files, but also deletes them if you take too long to make the ransom payment of $150 USD.  The Jigsaw Ransomware, named after the iconic character that appears in the ransom note, will delete files every hour and each time the infection starts until you pay the ransom.  At this time is currently unknown how this ransomware is distributed.

This is the first time that we have seen these types of threats actually being carried out by a ransomware infection. The good news is that a method has been discovered that allows victims to decrypt their files for free.

Jigsaw Ransomware is serious about its threats…
It is not the first time that we have seen ransomware threaten to delete files, but this is the first time that one has actually carried out its threats.  The Jigsaw Ransomware deletes files every 60 minutes and when the program is restarted.

Every hour,  the Jigsaw Ransomware will delete a file on your computer and increment a counter. Over time this counter will cause more than one file to be deleted every hour.

More destructive, though, is the amount of files that are deleted every time the ransomware starts. After the initial infection, when the ransomware it restarted, whether that be from a reboot or terminating the process, Jigsaw will delete a thousand, yes a thousand, files from the victim’s computer.

This process is very destructive and obviously being used to pressure the victim into paying the ransom.

How to decrypt and remove the Jigsaw Ransomware
Thankfully, through the analysis of MalwareHunterTeam, DemonSlay335, and myself it was discovered that it is possible to decrypt this ransomware for free.  Using this information, Demonslay335 has released a decryptor that can decrypt files encrypted by the Jigsaw Ransomware.  To decrypt your files, the first thing that you should do is terminate the firefox.exe and drpbx.exe processes in Task Manager to prevent any further files from being deleted.  You should then run MSConfig and disable the startup entry called firefox.exe that points to the %UserProfile%\AppData\Roaming\Frfx\firefox.exe executable.

Once you have terminated the ransomware and disabled its startup, let’s proceed with decrypting the files.  The first step is to download and extract the Jigsaw Decryptor from the following URL:

http://www.bleepingcomputer.com/download/jigsaw-decrypter/

Then double-click on the JigSawDecrypter.exe file to launch the program.  When the program launches you will be greeted with a screen similar to the one shown to the right.

To decrypt your files simply select the directory and click on the Decrypt My Files button. If you wish to decrypt the whole drive, then you can select the C: drive itself.  It is advised that you do not put a checkmark in the Delete Encrypted Files option until you have confirmed that the tool can properly decrypt your files.

When it has finished decrypting your files, the screen will appear like the screen to the left.

Now that your files are decrypted, I suggest that you run an antivirus or anti-malware program to scan your computer for infections.