According to the experts at Forcepoint, the author is offering the malware in many Tor-based crime forums as source code allowing crooks to request a customized version of the code.
The CradleCore ransomware is offered by the author as a C++ source code along with the necessary PHP web server scripts and a payment panel, the malware goes for 0.35 Bitcoin (around $400) but the price is negotiable.
“Typically, ransomware is monetized by developers using the RaaS business model. If that doesn’t work, only then the will the developers consider selling the source code.” reads the analysis published by Forcepoint.
CradleCore is offered as a C++ source code with PHP server scripts and a payment panel. It started to be sold on a few Tor-based sites over two weeks ago for a negotiable price starting at 0.35 BTC (approximately 428 USD)”
According to the experts, this model of sale will lead to the development of new variants derived from CradleCore.
The ransomware is offered with a relatively complete feature set, it uses Blowfish for file encryption and allows offline encryption too.
The malicious code implements an anti-sandbox mechanism and communicates to command and control server via a Tor2Web gateway.
Once infected a system, the CradleCore ransomware encrypts files and to drops a ransom note on the system. When the malware encrypts the files it appends the .cradle extension to them.
Experts from Forcepoint that analyzed the readme file, believe that the author of the malware is a developer without a significant experience in malware coding.
The researchers discovered more about the author by conducting further analysis on the advertisement site for CradleCore ransomware.
“While the advertisement site for CradleCore is hosted on the dark web, the site’s Apache server status page appears to be accessible to the public. The logs appeared to show that the Apache server hosting the Onion site has a second Virtual Host (VHost) hosting a clearnet website. VHosts, to those unfamiliar, allow multiple websites to be hosted on a single machine and IP address:” reads the analysis.
“The Linode-assigned IP address hosting the clearnet site appears to be exclusive-use. Essentially, this could mean either that the server is compromised and is abused to host the CradleCore website or that the clearnet website and CradleCore belong to the same owner.
Digging around the contents of that clearnet website led us to the website owner’s personal site who appears to be working as a freelance software developer. From the information available on his personal website we managed to find his Twitter and LinkedIn account where it is indicated that he is a C++ programmer.”
Of course, this means that the owner of the clearnet site that is used to sell the ransomware is linked to a freelance C++ developer, but there is no proof that he is also the coder.
Concluding Forcepoint researchers believe the ransomware may be the first project of a novice malware developer.
“CradleCore is yet another new ransomware product that is available to cybercriminals. It is being sold as source code which potentially suggests that CradleCore may be a first- or side-project of someone with limited experience of malware business models looking for extra income. It also means that anyone who purchases it will not only be able to update the ransomware but also share the source code to others,” Forcepoint says.
(Security Affairs – CradleCore ransomware, cybercrime)