The source code for an information-stealing malware coded in Rust has been released for free on hacking forums, with security analysts already reporting that the malware is actively used in attacks.
The malware, which the author claims to have developed in just six hours, is quite stealthy, with VirusTotal returning a detection rate of around 22%.
As the info-stealer is written in Rust, a cross-platform language, it allows threat actors to target multiple operating systems. However, in its current form, the new info-stealer only targets Windows operating systems.
Analysts at cybersecurity firm Cyble, who sampled the new info-stealer and named it “Luca Stealer,” report that the malware comes with standard capabilities for this type of malware.
When executed, the malware attempts to steal data from thirty Chromium-based web browsers, where it will steal stored credit cards, login credentials, and cookies.
The stealer also targets a range of “cold” cryptocurrency and “hot” wallet browser addons, Steam accounts, Discord tokens, Ubisoft Play, and more.
Where Luca Stealer stands out against other info-stealers is the focus on password manager browser addons, stealing the locally stored data for 17 applications of this kind.
In addition to targeting applications, Luca also captures screenshots and saves them as a .png file, and performs a “whoami” to profile the host system and send the details to its operators.
One notable capability typically found in other info-stealers but is not available in Luca is a clipper used to modify clipboard contents to hijack cryptocurrency transactions.
The exfiltration of the stolen data is done via Discord webhooks or Telegram bots, depending on whether the exfiltrated file is above 50MB or not. The malware will use a Discord webhook to send the data back to the attackers for larger logs of stolen data.
The stolen data is packed inside a ZIP archive accompanied by a summary of what’s included, so the operator can evaluate the extent of the loot at a single glance.
Should we be concerned?
Cyble reports that it has seen at least 25 instances of Luca Stealer used in the wild, so while some cybercriminals took up the free offer, it’s unknown if this new malware will see massive deployment.
However, The fact that it’s offered for free with source code, whereas most info-stealers are sold at a monthly subscription cost, could be a driver, but Luca isn’t the only one to be given away at no charge.
Finally, Luca is written in Rust, which means that porting it to Linux or macOS isn’t complicated, so the original author or someone else might perform that conversion in the future.