The GandCrab4 Ransomware is a ransomware Trojan, which is the fourth variant of the GandCrab Ransomware released. The GandCrab4 Ransomware was observed on July 2, 2018, and seems to have better obfuscation and encryption than its predecessors. The GandCrab4 Ransomware seems to be designed to carry out its attack offline, and it also seems that the criminals responsible for this attack are now targeting it towards high-profile victims rather than individual computer users.
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The GandCrab4 Ransomware's Intended Targets
The GandCrab4 Ransomware is capable of attacking most computers running the Windows operating system. The GandCrab4 Ransomware seems to be optimized to carry out its attack on some server environments, and it is likely that Web servers and databases associated with companies or websites are the intended targets, which is likelier to make the criminals more money than attacking individual computer users. Like its predecessors, the main way in which the GandCrab4 Ransomware is distributed is through corrupted email attachments and, in the case of the GandCrab4 Ransomware, also as pirated software and video game cracked versions. The GandCrab4 Ransomware has been observed being distributed online disguised as an aiming bot for popular first-person shooter games specifically.
How the GandCrab4 Ransomware Carries Out Its Atta
The GandCrab4 Ransomware targets the user-generated files, using strong encryption to make the victim's files inaccessible. The GandCrab4 Ransomware will encrypt a wide variety of media files, databases, documents, and numerous other file types. The files that threats like the GandCrab4 Ransomware will target in their attacks include:
.3dm, .3g2, .3gp, .7zip, .aaf, .accdb, .aep, .aepx, .aet, .ai, .aif, .as, .as3, .asf, .asp, .asx, .avi, .bmp, .c, .class, .cpp, .cs, .csv, .dat, .db, .dbf, .doc, .docb, .docm, .docx, .dot, .dotm, .dotx, .dwg, .dxf, .efx, .eps, .fla, .flv, .gif, .h, .idml, .iff, .indb, .indd, .indl, .indt, .inx, .jar, .java, .jpeg, .jpg, .js, .m3u, .m3u8, .m4u, .max, .mdb, .mid, .mkv, .mov, .mp3, .mp4, .mpa, .mpeg, .mpg, .msg, .pdb, .pdf, .php, .plb, .pmd, .png, .pot, .potm, .potx, .ppam, .ppj, .pps, .ppsm, .ppsx, .ppt, .pptm, .pptx, .prel, .prproj, .ps, .psd, .py, .ra, .rar, .raw, .rb, .rtf, .sdf, .sdf, .ses, .sldm, .sldx, .sql, .svg, .swf, .tif, .txt, .vcf, .vob, .wav, .wma, .wmv, .wpd, .wps, .xla, .xlam, .xll, .xlm, .xls, .xlsb, .xlsm, .xlsx, .xlt, .xltm, .xltx, .xlw, .xml, .xqx, .xqx, .zip.
The GandCrab4 Ransomware will mark the files it encrypts with the file extension '.KRAB' added to the end of the file's name.
The GandCrab4 Ransomware's Ransom Demand
After the GandCrab4 Ransomware encrypts the victim's files, the GandCrab4 Ransomware delivers a ransom note. The GandCrab4 Ransomware's ransom note takes the form of a text file named 'KRAB-DECRYPT.txt.' which will appear on the infected computer's desktop. The text of the GandCrab4 Ransomware ransom note reads:
'—= GANDCRAB V4=—
All your files documents, photos, databases and other important files are encrypted and have the extension: .KRAB
The only method of recovering files is to purchase a private key. It is on our server and only we can recover your files.
The server with your key is in a closed network TOR. You can get there by the following ways:
1. Download Tor browser – h[tt]ps://www.torproject[.]org/
2. Install Tor browser
3. Open Tor Browser
4. Open link in tor browser: h[tt]ps://gandcrabmfe6mnef[.]onion/[unique string]
5. Follow the instructions on this page.
On our page you will see instructions on payment and get the opportunity to decrypt 1 file for free.'
The victims of the GandCrab4 Ransomware attack are asked to pay 800 USD approximately in Bitcoin in exchange for a decryption tool. However, this payment is not recommended at all, as well as contact with the criminals. In most cases, the criminals will not restore the victim's files, and they will likely target the victim with additional malware. Furthermore, paying these ransoms allows the criminals to continue creating and distributing threats like the GandCrab4 Ransomware. To protect your machine against these threats, you should have file backups on the cloud or an offline location.