A newly detected malware loader, Win/TrojanDownloader.Rugmi, is utilized by threat actors to distribute various information stealers like Lumma Stealer, Vidar, RecordBreaker, and Rescoms. ESET identified Rugmi as a loader consisting of three components: a downloader for encrypted payloads, an internal resource-based loader, and an external file loader, contributing to its evasion tactics against detection.
ESET’s telemetry data showed a significant surge in Rugmi loader detections, escalating from minimal daily counts to hundreds in October and November 2023. This surge in Rugmi’s prevalence aligns with the broader trend of stealer malware being offered as a service, particularly Lumma Stealer, available in underground forums for $250 monthly, with a premium plan offering source code access for $20,000.
ESET discovered indications suggesting Lumma’s codebase repurposed elements from Mars, Arkei, and Vidar, amplifying its capabilities. The distribution tactics of these malware variants include diverse methods like malvertising, counterfeit software installations, and Discord’s CDN misuse for propagation. Additionally, recent findings by McAfee Labs unveiled a new NetSupport RAT variant stemming from NetSupport Manager, employed by initial access brokers targeting the U.S. and Canada.
This RAT variant starts with obfuscated JavaScript files, enabling the retrieval of remote control and stealers via PowerShell commands from a controlled server, signifying evolving tactics among cybercriminals. These disclosures spotlight the ease of access to sophisticated malware and the adaptability of cyber threats, emphasizing the necessity for heightened vigilance and security measures.
