Geek's Advice

OOSS ransomware hits hard – turns personal files useless

OOSS ransomware is a file-encrypting computer virus which originates from DJVU ransomware group. The aim of this virus is to infect the computer by deceiving the user, then disable security programs to start data encryption procedure. During this procedure, the virus encrypts all files except Windows system folders, adds .ooss file extensions to original filenames, then creates _readme.txt notes. These notes inform the victim about the only way to decrypt files – pay a hefty ransom to the cybercriminals (ranging between $490-$980). The ransom note doesn’t inform about additional malware the ransomware installs on the system, called AZORULT.

If you get hit by OOSS file extension ransomware, you will soon discover that you can no longer open any of your personal files. Be it documents, photos or videos – none of these will be accessible. This is the aim of the virus – to cause you a frustration and scare you, then convince you to pay the specified ransom to the provided cryptowallet.

The cybercriminals suggest the decryption software along the specific key for $490 in Bitcoin (if paid within 3 days from the initial attack date). If the victim doesn’t succeed in collecting sum of money within 72 hours, purchasing cryptocurrency and paying the criminals, the price goes up to $980.

The attackers also offer testing their tool for free on one small file that doesn’t contain important information. The file along victim’s personal ID should be sent to one of the email addresses that the criminals left in the _readme.txt file – helpdatarestore@firemail.cc or helpmanager@mail.ch .

The offline and online key usage explained

OOSS file extension virus encrypts files using online or offline keys based on its success to connect to its Command&Control server during the attack. If the connection is successful, the virus takes an unique encryption key from the server for each victim separately. If the connection fails, the virus uses hardcoded key in the malware source code itself.

The sad fact is that only the cybercriminals are able to recover the files for you. They are the only ones having the OOSS decryption keys. You can also restore your data for free if you have data backups. If you do not, unfortunately, there are no options to recover files.

Threat Summary

OOSS data decryption is nearly impossible

As mentioned earlier, OOSS ransomware uses extremely strong encryption method to lock your files securely. As sadly as it sounds, the whole operation is done smoothly and without any flaws. The only rescue for victims is data backups. However, it still seems that majority of computer users do not care enough to create them in time.

Speaking of other data decryption alternatives, you should check C:/SystemID/PersonalID.txt file for an ID which could indicate offline data encryption. The sign you should be looking for is a string ending in t1. If you manage to find it in the specified file, you might recover your files one day using STOP decryptor. However, only after someone with offline encryption also pays and shares the key with Emsisoft team).

How to avoid ransomware attacks

Avoiding ransomware attacks, in general, is quite simple. Avoiding STOP/DJVU ransomware, such as MMNN, OOSS, ROOE, BBOO, is even easier. This malware group tends to attack victims via very specific files. It has been noticed that all victims download this malware alongside software cracks, keygens, and other illegal tools used to activate software licenses without actually paying for it.

Remember that risking to save some money in such way can easily result in a much bigger loss. Cybercriminals use such downloads for malware distribution very frequently. No one knows when you’re going to encounter such deceptive download packed with ransomware.

In general, to avoid ransomware attacks, you should:

• Keep your software up-to-date.
• Create data backups on external storage devices regularly.
• Never click on suspicious links online.
• Do not risk downloading shady-looking files from the Internet.
• Do not open links or attachments inserted into emails from people you do not know, even if these come in a form of a business-related matters.

Best Way to Remove OOSS Ransomware Virus

The easiest way to remove OOSS ransomware virus is to start your PC in protected environment and run an antivirus or anti-malware tool capable of detecting STOP/DJVU malware strain as well as Azorult Trojan. Please remember that the following Trojan steals passwords, so make sure you change them on all of your accounts.

OOSS virus removal leaves a safe environment to plug your storage device with data backup for successful data restoration. In case you are one of the victims who do not have a backup, then restoring files in the future is nearly impossible.

OUR GEEKS RECOMMEND

Our team recommends a two-step rescue plan to remove ransomware and other remaining malware from your computer, plus repair caused virus damage to the system:

STEP 1. REMOVE AUTOMATICALLY WITH ROBUST ANTIVIRUS

REMOVE & PROTECT WITH INTEGO

Get INTEGO ANTIVIRUS for Windows to remove ransomware, Trojans, adware and other spyware and malware variants and protect your PC and network drives 24/7.. This VB100-certified security software uses state-of-art technology to provide protection against ransomware, Zero-Day attacks and advanced threats, Intego Web Shield blocks dangerous websites, phishing attacks, malicious downloads and installation of potentially unwanted programs.

Use INTEGO Antivirus to remove detected threats from your computer.

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STEP 2. REPAIR VIRUS DAMAGE TO YOUR COMPUTER

DOWNLOAD RESTORO

RESTORO provides a free scan that helps to identify hardware, security and stability issues and presents a comprehensive report which can help you to locate and fix detected issues manually. It is a great PC repair software to use after you remove malware with professional antivirus. The full version of software will fix detected issues and repair virus damage caused to your Windows OS files automatically.

RESTORO uses AVIRA scanning engine to detect existing spyware and malware. If any are found, the software will eliminate them.

Read full review here.

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Alternative software recommendations

Malwarebytes Anti-Malware

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System Mechanic Ultimate Defense

If you're looking for an all-in-one system maintenance suite that has 7 core components providing powerful real-time protection, on-demand malware removal, system optimization, data recovery, password manager, online privacy protection and secure driver wiping technology. Therefore, due to its wide-range of capabilities, System Mechanic Ultimate Defense deserves Geek's Advice approval. Get it now for 50% off. You may also be interested in its full review.

Disclaimer. This site includes affiliate links. We may earn a small commission by recommending certain products, at no additional cost for you. We only choose quality software and services to recommend.

Norbert Webb

Norbert Webb is the head of Geek’s Advice team. He is the chief editor of the website who controls the quality of content published. The man also loves reading cybersecurity news, testing new software and sharing his insights on them. Norbert says that following his passion for information technology was one of the best decisions he has ever made. “I don’t feel like working while I’m doing something I love.” However, the geek has other interests, such as snowboarding and traveling.