Attacks using TeslaCrypt ransomware intensify

The number of daily TeslaCrypt attacks have increased nine times in two weeks

Over the past two weeks security researchers have seen a surge in attacks using a file-encrypting ransomware program called TeslaCrypt, known for targeting gamers in the past.

TeslaCrypt first appeared in March and stood out because over 50 of the 185 file types it targeted were associated with computer games and related software, including game saves, custom maps, profiles, replays and mods -- content that users might have a hard time replacing.

In April researchers from Cisco found a weakness in TeslaCrypt's encryption routine and created a tool that could decrypt files affected by some versions of the program.

Since then, the ransomware program's authors have continued to refine it and started selling it on the underground market to other cybercriminals. However, the number of attacks have stayed relatively low until late November when security researchers from Symantec observed a significant change.

Over the past two weeks the number of TeslaCrypt infection attempts detected by Symantec went up from around 200 a day to 1,800, suggesting that one cybercriminal group is ramping up its use of this malicious program.

The group's preferred method of infection is through spam emails with malicious attachments. The subject lines of these emails begin with "ID," followed by a random number and a request related to alleged invoices, successful orders or wire transfers.

Judging by these topics, the attackers are targeting businesses -- a new trend for ransomware attacks in general that's fueled by businesses being more willing to pay to recover important files.

The malicious TeslaCrypt email attachments may include the words "invoice," "doc," or "info," but they actually contain heavily obfuscated JavaScript code designed to evade antivirus detection and download the ransomware program.

If the attack is successful, the program will encrypt all files with a strong encryption algorithm and will add the .VVV extension to them. It will also drop text and HTML ransom notes that instruct victims how to access Tor-hosted sites in order to pay the ransom.

"Given that this group using TeslaCrypt has been highly active in recent weeks, businesses and consumers should be on their guard, keep their security software regularly updated, and exercise caution when opening emails from unfamiliar sources," the Symantec researchers said in a blog post. "Users should also regularly back up any files stored on their computers. If a computer is compromised with ransomware, then these files can be restored once the malware is removed from the computer."

Join the Good Gear Guide newsletter!

Error: Please check your email address.

Our Back to Business guide highlights the best products for you to boost your productivity at home, on the road, at the office, or in the classroom.

Keep up with the latest tech news, reviews and previews by subscribing to the Good Gear Guide newsletter.

Lucian Constantin

IDG News Service
Show Comments

Essentials

Lexar® JumpDrive® S57 USB 3.0 flash drive

Learn more >

Microsoft L5V-00027 Sculpt Ergonomic Keyboard Desktop

Learn more >

Mobile

Lexar® JumpDrive® S45 USB 3.0 flash drive 

Learn more >

Exec

HD Pan/Tilt Wi-Fi Camera with Night Vision NC450

Learn more >

Lexar® JumpDrive® C20c USB Type-C flash drive 

Learn more >

Audio-Technica ATH-ANC70 Noise Cancelling Headphones

Learn more >

Lexar® Professional 1800x microSDHC™/microSDXC™ UHS-II cards 

Learn more >

Budget

Back To Business Guide

Click for more ›

Most Popular Reviews

Latest News Articles

Resources

PCW Evaluation Team

Azadeh Williams

HP OfficeJet Pro 8730

A smarter way to print for busy small business owners, combining speedy printing with scanning and copying, making it easier to produce high quality documents and images at a touch of a button.

Andrew Grant

HP OfficeJet Pro 8730

I've had a multifunction printer in the office going on 10 years now. It was a neat bit of kit back in the day -- print, copy, scan, fax -- when printing over WiFi felt a bit like magic. It’s seen better days though and an upgrade’s well overdue. This HP OfficeJet Pro 8730 looks like it ticks all the same boxes: print, copy, scan, and fax. (Really? Does anyone fax anything any more? I guess it's good to know the facility’s there, just in case.) Printing over WiFi is more-or- less standard these days.

Ed Dawson

HP OfficeJet Pro 8730

As a freelance writer who is always on the go, I like my technology to be both efficient and effective so I can do my job well. The HP OfficeJet Pro 8730 Inkjet Printer ticks all the boxes in terms of form factor, performance and user interface.

Michael Hargreaves

Windows 10 for Business / Dell XPS 13

I’d happily recommend this touchscreen laptop and Windows 10 as a great way to get serious work done at a desk or on the road.

Aysha Strobbe

Windows 10 / HP Spectre x360

Ultimately, I think the Windows 10 environment is excellent for me as it caters for so many different uses. The inclusion of the Xbox app is also great for when you need some downtime too!

Mark Escubio

Windows 10 / Lenovo Yoga 910

For me, the Xbox Play Anywhere is a great new feature as it allows you to play your current Xbox games with higher resolutions and better graphics without forking out extra cash for another copy. Although available titles are still scarce, but I’m sure it will grow in time.

Featured Content

Latest Jobs

Don’t have an account? Sign up here

Don't have an account? Sign up now

Forgot password?