Dharma virus, unlike similar types of ransomware, does not change desktop background, but creates README.txt or Document.txt.[firstname.lastname@example.org].zzzzz files and places them in each folder with compromised files. Text files contain message stating that users have to pay the ransom using Bitcoins and amount is approximately $300-$500 depending on ransomware version. The private decryption key is stored on a remote server, and there currently impossible to break the encryption of the latest version.
Java Ransomware is extremely harmful file-encrypting virus, that belongs to the family of Dharma/Crysis ransomware. It adds .java extension to all encrypted files. Usually, this is complex suffix that contains unique id and e-mail. Java Ransomware uses spam mailing with malicious .docx attachments. Such attachments have malicios macros, that runs when user opens the file. This macros downloads executable from the remote server, that, in its turn, starts encryption process.
Arena Ransomware belongs to CrySis family, previous wide-spread ransomware of this type was Dharma Ransomware, that we described on this blog. Arena Ransomware was detected by security researches first time in August 2017. Since then, it had numerous updates. Different versions of Arena Ransomware demand different ransom amounts. It varies from 0,20 to 0,73 BitCoins, which is near $5000. Security experts do not recommend to pay developers of ransomware, as this encourages them to create new variations and does not guarantee decryption of your files. Actually, most times malefactors don’t send decryption keys. Latest versions of Arena Ransomware are not decryptable, however there is a chance to restore files affected by older versions.