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 newsletter!

Or

Sign up to gain exclusive access to email subscriptions, event invitations, competitions, giveaways, and much more.

Membership is free, and your security and privacy remain protected. View our privacy policy before signing up.

Error: Please check your email address.
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

Father’s Day Gift Guide

Brand Post

Most Popular Reviews

Latest Articles

Resources

PCW Evaluation Team

Luke Hill

MSI GT75 TITAN

I need power and lots of it. As a Front End Web developer anything less just won’t cut it which is why the MSI GT75 is an outstanding laptop for me. It’s a sleek and futuristic looking, high quality, beast that has a touch of sci-fi flare about it.

Emily Tyson

MSI GE63 Raider

If you’re looking to invest in your next work horse laptop for work or home use, you can’t go wrong with the MSI GE63.

Laura Johnston

MSI GS65 Stealth Thin

If you can afford the price tag, it is well worth the money. It out performs any other laptop I have tried for gaming, and the transportable design and incredible display also make it ideal for work.

Andrew Teoh

Brother MFC-L9570CDW Multifunction Printer

Touch screen visibility and operation was great and easy to navigate. Each menu and sub-menu was in an understandable order and category

Louise Coady

Brother MFC-L9570CDW Multifunction Printer

The printer was convenient, produced clear and vibrant images and was very easy to use

Edwina Hargreaves

WD My Cloud Home

I would recommend this device for families and small businesses who want one safe place to store all their important digital content and a way to easily share it with friends, family, business partners, or customers.

Featured Content

Product Launch Showcase

Don’t have an account? Sign up here

Don't have an account? Sign up now

Forgot password?