Necurs bot well known for biggest single malware spam campaigns contains nearly 5 million infected bots, of which one million active each day. In the past, it is responsible for spreading various ransomware like JAFF Ransomware, banking trojan Trickbot now it is distributing Scarab Ransomware.
Security researchers from F-Secure, Forcepoint, MalwareHunterTeam and myonlinesecurity spotted Necurs evolving and spreading another piece of Ransomware called Scarab.
Distribution Scarab Ransomware
Ransomware distributed through Email campaigns subjected “Scanned from (Lexmark/HP/Canon/Epson)” contains .vbs script downloaders compressed with 7zip “image2017-11-23-(7 random digits).7z“.
According to Forcepoint telemetry analysis, major traffic is sent to .com and followed by country based TLD like United Kingdom, Australia, France, and Germany. They intercepted more than 12.5 million Emails.
Execution Scarab Ransomware
The visual basic script that presents in the zip file executes and downloads the sevnz.exe(Scarab Ransomware) and creates autostart entries in the registry.
Necurs now spreading Scarab (https://t.co/M8YD8SS98p).
Interesting…
🤔
Let's see if it will be more successful than Locky in past months…@BleepinComputer @demonslay335
cc @MalwareTechBlog pic.twitter.com/e9rPiem9BX— MalwareHunterTeam (@malwrhunterteam) November 23, 2017
Once it executed it will encrypt the files and appends an extension .[[email protected]].scarab. Then once encryption completed it drops a Ransom note “IF YOU WANT TO GET ALL YOUR FILES BACK, PLEASE READ THIS.TXT” and the ransom note to opens automatically.
Scarab disables default windows recovery options and also it deletes original copy of the file. Sadly at this time, there are no decryptors available for the scarab.
Also Read HP Exposed more than 400,000 Customers Sensitive Information Online
Attackers offerd Multiple way’s to communicate
1. Misspelled Support email address ([email protected])
2. Bitmessage at BM-2cTu8prUGDS6XmXqPrZiyXXeqyFw5dXEba
VBScript SHA-256
c7e3c4bad00c92a1956b6d98aae0423170de060d2e15c175001aaeaf76722a52
Scarab SHA-256
7a60e9f0c00bcf5791d898c84c26f484b4c671223f6121dc3608970d8bf8fe4f
Common Defence’s to stay safe
- Don’t open the attachments that you are not expecting.
- Patch or Update your software.
- Use a reputable security suite.
- Download applications from Reputed sites.
- Stay strict with CIA Cycle.
