Geek's Advice

GHAS ransomware seeks to lock all of your computer files for a ransom

GHAS ransomware is a file-encrypting malicious virus that has been ascertained as a member of the notorious STOP/DJVU ransomware group. Its method of attack is similar to the other variants as it is known to encrypt every file contained in any computer it infects and equally appends the filenames with .ghas extension. Take for example, a file that is initially known as 1.jpg will automatically become 1.jpg.ghas and same will apply to all others. At the time of the attack, ransom notes known as _readme.txt will also be saved in all of the computer folders.

The ransom note contains message sent by the criminals explaining the development and why the victim would have to contact them so they could pay ransom and be able to receive the GHAS file decryption tool. Also, two email addresses will be included (support@sysmail.ch and supportsys@airmail.cc) ostensibly for the victim to use when responding to them.

Also included in the note are the decryption service prices and the accompanying terms of payment. The cybercriminals will state ransom fees payable by the victim would depend on how soon they’re able to do so. They would be required to pay $490 (50% of the usual ransom fee) if the payment can be made within 3 days of being notified but once it exceeds the timeframe, only the full amount i.e. $980 would be acceptable.

If/when contacted by the victim, using any of the emails provided, they will direct the victim to purchase cryptocurrency worth the ransom fee and transfer same to a wallet address that would be provided by them. The apparent reason why they use such a medium of payment is to avert possible tracking and arrest by law enforcement agencies who may come after them. To convince the victim and make them pay without further delay, they may request one sample of the encrypted files to be sent to them for test decryption but will also emphasize that such excerpt must not contain data/documents they may deem as important to the victim.

However, security experts both in-house and others often advice victims to follow FBI’s guidelines relative to such issues and the general verdict is NO TO ANY FORM OF RANSOM PAYMENT. This rigid conclusion is due to several factors as listed below:

• There are no guarantees you will recover your encrypted files even after parting with your money.
• Paying cybercriminals would only encourage them in their criminal activities since it is profitable.
• More funds available to cybercriminals will only make the situation worse because it will enable them to employ more hands and increase their capacity thereby affecting more people.

Aside the factors listed above, the virus typically releases Trojans like AZORULT and VIDAR as secondary motives in order to steal sensitive information such as banking details, cryptocurrency wallets, software login details, browsing history and passwords among others. The loss of such important information could lead to more problems like blackmails and theft. Therefore, it is imperative not to encourage them in any form.

For those who for one reason or another, were unfortunate to become victims had their computer systems infected with any variant of STOP/DJVU, including the one being discussed, you’re hereby advised to remove GHAS ransomware virus right away. The most effective way of doing so is to set up your computer in Safe Mode with the Networking option before running any genuine antivirus software on it. However, it is crucial to ensure that only GENUINE software copies are used for this purpose. As an additional step, we recommend downloading RESTORO in repairing Windows OS files damaged during a ransomware attack.

Ransomware Summary

REPAIR VIRUS DAMAGE

Ransomware distribution methods

The most common method through which STOP/DJVU ransomware variants such as GHAS virus end up infecting computers is when their users download the software through online malicious torrents. Such platforms are often used by cybercriminals in spreading malware.

They would camouflage the virus in pirated software copies, including the so-called key generators and “cracks” and afterward wait for unsuspecting users to download them. Once such unwholesome software contents are downloaded in individual computers, they trigger severe ransomware attacks. Based on reports by victims so far, popular software content are often pirated and uploaded to different online torrents platforms. Some of them are listed below, in no particular order:

• Internet Download Manager;
• Fifa 20;
• Tenorshare 4ukey;
• AutoCad;
• Cubase;
• Corel Draw;
• VMware Workstation;
• Opera browser;
• Adobe Illustrator;
• League of Legends;
• Adobe Photoshop;
• KMSPico (illegal Windows activation tool).

From the explanations so far, it is evident that the use of online torrents platforms for downloading of software is dangerous and should be stopped immediately. Also, trying to make use of such pirated contents is considered illegal and subject to criminal prosecution based on existing laws. Another factor that is often overlooked is the fact that whatever fees you’re asked by the original software producers would always be insignificant relative to the insane ransom fees often demanded by cybercriminals from their victims. Therefore it is imperative for users to only source for their software needs through the official pages of the original producers or their third-party affiliated agents. Another incentive to remember is that using the legitimate channels would not put your important or sensitive information at risk.

Another method used by cybercriminals in spreading ransomware is through malicious email attachments. In this option, they will make use of files such as DOCX, PDF or XLS in composing highly convincing emails. They prefer these ones because they enable macro functions and JavaScript that are essential in downloading and releasing payload in end-user computers.

The difficult part is how to decipher if an incoming email is genuine or a malware triggering fake email sent by cybercriminals. Why it is so is because cybercriminals now impersonate individuals or well-known corporate brands such as Amazon, eBay, UPS or DHL to mention just a few. They would also give such emails and accompanying attachments inciting names like Invoice, Tracking Details or Order Summary just to deceive their victims. Alternatively, they also make use of email spoofing ways in obfuscating the actual sender’s email address. Whatever gimmick they use, computer users are advised to be wary at all times and shouldn’t disregard any obvious red flag.

Lastly, those that are victims already should shun any website advertising any form of decryption solutions because they’re likely to be fraudulent. At the moment, only the pair of Emsisoft and DiskTuna offer STOP/DJVU decryption solutions that have been verified to work. For more details about them, you can use this link provided here. Cybercriminals also distribute other versions of ransomware in the guise of nonexistent STOP/DJVU decryptors.

More details to know about the infection

Computer users that want to understand more about what happens during the GHAS ransomware attack, particularly the technical aspects, this section would prove helpful. Typically, the first action the malware takes is to launch build.exe or build2.exe followed by winupdate.exe i.e. the screen update that shows fake Windows. Afterward, it will make a connection to https[:]//api.2ip.ua/geo.json before saving the response in the geo.json file. The file includes the computer’s geolocation, time zone, latitude, and longitude, as well as time zone.

Another one called information.txt will also be created for active processes, installed software list, and hardware details.

Going forward, the malware will now profile the country code it obtained against a list of countries they designated as encryption-exempted, namely; Russian Federation, Syria, Armenia, Ukraine, Kazachstan, Kyrgyzstan, Tajikistan, Uzbekistan and Belarus. If peradventure it establishes that it belongs to any of the listed countries, it would instantly terminate its mission but if otherwise, it would move to the next stage by extracting online encryption key which would be merged with the victim’s ID before saving it in bowsakkdestx.txt file and to PersonalID.txt file. Shown below are examples of these files.

However, in situations whereby it fails to obtain any online encryption key, the virus will resort to the use of a hardcoded offline key as a replacement. The striking difference between both keys is that while the online version is unique per victim, the offline version is uniform for all victims of a particular virus variant. The appearance of t1 characters appended to the personal ID is an indication that an offline key was used, and it raises hope that someday .ghas files would be decrypted. More information about it is provided below the article.

The ransomware will at this point commence full data encryption by scanning each folder and encrypting every file with Salsa20 before making use of the RSA-2048 key to lock them respectively.

The image below is a display of the _readme.txt ransom note the malware typically drops in all the folders.

In concluding the entire process, the malware will blacklist some notable domains by adding them to the Windows HOSTS file and linking them to localhost IP thereby effectively barring the victim from having access to them. The error message DNS_PROBE_FINISHED_NXDOMAIN may appear whenever they make any attempt to visit them. It makes this proactive but cunning move to ensure that victims don’t get any help online. Additional malware such as VIDAR or AZORULT would also be dropped.

Remove GHAS ransomware virus and also recover your files

Victims whose files were encrypted by the malware variant being discussed are advised to report the cyberattack to relevant government agencies responsible for handling such issues and also remove GHAS ransomware without any delay. More comprehensive steps on how to go about it are provided below.

Now you’ve removed GHAS ransomware virus; please follow these recommendations as outlined by our team:

• Get in touch with any relevant government agency and report the cyber-attack.
• Make use of any available storage device in restoring the lost files but you should ensure the virus is completely removed before plugging such device.
• Change all passwords that were used in the compromised computer to avoid or limit damages.

In conclusion, always remember to set up your computer in Safe Mode with Networking before scanning the system with a genuine antivirus software. The importance of making use of only strong and genuine antivirus software is paramount in ensuring that the entire process is successful. You should also consider the necessity of downloading RESTORO for repairing of damaged Windows system files. However, in all you do always avoid risk factors (as mentioned in this article) that could expose your computer to a possible ransomware attack.

OUR GEEKS RECOMMEND

Our team recommends removing malware using a professional antivirus software and then using the following tool to repair virus damage to Windows system files:

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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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.