A newly discovered ransomware family is generating a different encryption key for each of the encrypted files but saves none of them, thus making data recovery impossible.
Dubbed Thanatos, the malware was discovered by MalwareHunterTeam and already analyzed by several other security researchers.
When encrypting files on a computer, the malware appends the .THANATOS extension to them. After completing the encryption, the malware connects to a specific URL to report back, thus allowing attackers to keep track of the number of infected victims.
The malware also generates an autorun key to open the ransom note every time the user logs in. In that note, the victim is instructed to send $200 to a listed crypto-coin address. Victims are also instructed to contact the attackers via email to receive a decryption program.
Thanatos’ operators allow victims to pay the ransom in Bitcoin, Ethereum, or Bitcoin Cash, thus becoming the first ransomware to accept Bitcoin Cash payments, Bleeping Computer’s Lawrence Abrams points out.
The issue with the new ransomware is that it, because it doesn’t save the encryption keys, files cannot be decrypted normally. However, victims don’t know that and might end up paying the ransom in the hope they can recover their files.
The good news regarding Thanatos, however, is that there might be a way to brute force the encryption keys, at least this is what security researcher Francesco Muroni suggests. However, this process would take a long time and would require for it to be a common file type with a known magic header.
Because of the botched encryption process, it is recommended to avoid paying the ransom if infected with Thanatos. Of course, this applies to every ransomware infection. It is also recommended to always keep applications up to date, and to use a security program capable of preventing this type of malware from compromising your systems.
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