Free Bitdefender tool prevents Locky, other ransomware infections, for now

The tool tricks Locky, TeslaCrypt and CTB-Locker ransomware into believing that computers are already infected

Antivirus firm Bitdefender has released a free tool that can prevent computers from being infected with some of the most widespread file-encrypting ransomware programs: Locky, TeslaCrypt and CTB-Locker.

The new Bitdefender Anti-Ransomware vaccine is built on the same principle as a previous tool that the company designed to prevent CryptoWall infections. CryptoWall later changed the way in which it operates, rendering that tool ineffective, but the same defense concept still works for other ransomware families.

While security experts generally advise against paying ransomware authors for decryption keys, this is based more on ethical grounds than on a perceived risk that the keys won't be delivered.

In fact, the creators of some of the most successful ransomware programs go to great lengths to deliver on their promise and help paying users decrypt their data, often even engaging in negotiations that result in smaller payments. After all, the likelihood of more users paying is influenced by what past victims report.

Many ransomware creators also build checks into their programs to ensure that infected computers where files have already been encrypted are not infected again. Otherwise, some files could end up with nested encryption by the same ransomware program.

The new Bitdefender tool takes advantage of these ransomware checks by making it appear as if computers are already infected with current variants of Locky, TeslaCrypt or CTB-Locker. This prevents those programs from infecting them again.

The downside is that the tool can only fool certain ransomware families and is not guaranteed to work indefinitely. Therefore, it's best for users to take all the common precautions to prevent infections in the first place and to view the tool only as a last layer of defense that might save them in case everything else fails.

Users should always keep the software on their computer up to date, especially the OS, browser and browser plug-ins like Flash Player, Adobe Reader, Java and Silverlight. They should never enable the execution of macros in documents, unless they've verified their source and know that the documents in question are supposed to contain such code.

Emails, especially those that contain attachments, should be carefully scrutinized, regardless of who appears to have sent them. Performing day-to day activities from a limited user account on the OS, not from an administrative one, and running an up-to-date antivirus program, are also essential steps in preventing malware infections.

"While extremely effective, the anti-ransomware vaccine was designed as a complementary layer of defense for end-users who don’t run a security solution or who would like to complement their security solution with an anti-ransomware feature," said Bogdan Botezatu, a senior e-threat analyst at Bitdefender, via email.

Join the CSO newsletter!

Error: Please check your email address.

More about

Show Comments

Featured Whitepapers

Editor's Recommendations

Solution Centres

Stories by Lucian Constantin

Latest Videos

  • 150x50

    CSO Webinar: Will your data protection strategy be enough when disaster strikes?

    Speakers: - Paul O’Connor, Engagement leader - Performance Audit Group, Victorian Auditor-General’s Office (VAGO) - Nigel Phair, Managing Director, Centre for Internet Safety - Joshua Stenhouse, Technical Evangelist, Zerto - Anthony Caruana, CSO MC & Moderator

    Play Video

  • 150x50

    CSO Webinar: The Human Factor - Your people are your biggest security weakness

    ​Speakers: David Lacey, Researcher and former CISO Royal Mail David Turner - Global Risk Management Expert Mark Guntrip - Group Manager, Email Protection, Proofpoint

    Play Video

  • 150x50

    CSO Webinar: Current ransomware defences are failing – but machine learning can drive a more proactive solution

    Speakers • Ty Miller, Director, Threat Intelligence • Mark Gregory, Leader, Network Engineering Research Group, RMIT • Jeff Lanza, Retired FBI Agent (USA) • Andy Solterbeck, VP Asia Pacific, Cylance • David Braue, CSO MC/Moderator What to expect: ​Hear from industry experts on the local and global ransomware threat landscape. Explore a new approach to dealing with ransomware using machine-learning techniques and by thinking about the problem in a fundamentally different way. Apply techniques for gathering insight into ransomware behaviour and find out what elements must go into a truly effective ransomware defence. Get a first-hand look at how ransomware actually works in practice, and how machine-learning techniques can pick up on its activities long before your employees do.

    Play Video

  • 150x50

    CSO Webinar: Get real about metadata to avoid a false sense of security

    Speakers: • Anthony Caruana – CSO MC and moderator • Ian Farquhar, Worldwide Virtual Security Team Lead, Gigamon • John Lindsay, Former CTO, iiNet • Skeeve Stevens, Futurist, Future Sumo • David Vaile - Vice chair of APF, Co-Convenor of the Cyberspace Law And Policy Community, UNSW Law Faculty This webinar covers: - A 101 on metadata - what it is and how to use it - Insight into a typical attack, what happens and what we would find when looking into the metadata - How to collect metadata, use this to detect attacks and get greater insight into how you can use this to protect your organisation - Learn how much raw data and metadata to retain and how long for - Get a reality check on how you're using your metadata and if this is enough to secure your organisation

    Play Video

  • 150x50

    CSO Webinar: How banking trojans work and how you can stop them

    CSO Webinar: How banking trojans work and how you can stop them Featuring: • John Baird, Director of Global Technology Production, Deutsche Bank • Samantha Macleod, GM Cyber Security, ME Bank • Sherrod DeGrippo, Director of Emerging Threats, Proofpoint (USA)

    Play Video

More videos

Blog Posts

Market Place