Chinese-speaking hackers linked to criminal activity have intensified their efforts to target compatriots with malware, raising concerns about the rising threat of Chinese criminal hacking. Proofpoint researchers have discovered a “minor resurgence” of the Sainbox remote access Trojan, along with a new Trojan called “ValleyRAT,” both of which are being delivered through emails predominantly written in Chinese.
Background on the Threat
Proofpoint’s identification of the resurgence of Sandbox and the emergence of ValleyRAT Trojans suggests that financially motivated Chinese hackers could potentially rival the threat posed by Russian hackers. Western nations associate Russian hacking with criminal underground activities within their borders, while Chinese hacking is commonly linked to cyberespionage and intellectual property theft.
Method of Attack
The malware delivery mechanism employed by these Chinese-speaking hackers primarily utilizes emails written in Chinese. This targeted approach significantly increases the chances of successful attacks, as the recipients are more likely to understand and engage with the malicious content. Proofpoint warns that the variability in the sources of such malware increases the difficulty in attributing the attacks to a single entity.
Potential Collaboration among Threat Actors
Evidence suggests that multiple threat actors may be utilizing the same infrastructure to deliver various malware families. This indicates potential collaboration or coordination among these hackers, emphasizing the sophistication and scale of their criminal activities. Proofpoint’s analysis uncovered more than 30 campaigns involving Sainbox, ValleyRAT, and the notorious Purple Fox malware, further substantiating the breadth of this threat.
Target Expansion
In addition to targeting Chinese-speaking individuals, these hackers have also demonstrated an interest in Japanese organizations. This expansion suggests their ambition to branch out from their primary target group, potentially seeking new avenues for financial gain or strategic objectives. The widening scope of their attacks underscores the need for increased vigilance not only among Chinese-speaking individuals but also within global organizations.
Malware Delivery Techniques
The hackers employ various deceiving lures to entice their victims, commonly using business-related themes such as invoices, payments, and new product announcements. The malware is concealed within seemingly innocuous Excel documents, PDF files, or malicious links, allowing the attackers to gain remote access and control over victims’ computers.
Flexible Delivery Methods
Recent activity clusters have highlighted hackers’ adaptability and use of both simple and moderately complex malware delivery techniques. This versatility enables them to bypass traditional security measures, making it increasingly challenging for organizations to detect and defend against these attacks effectively.
The mounting threat posed by Chinese criminal hacking, as evidenced by the resurgence of old and emergence of new Chinese-themed malware, demands a proactive and comprehensive response. Organizations need to remain vigilant and prioritize robust cybersecurity measures to protect against these evolving threats. Enhanced awareness and collaboration among cybersecurity professionals, along with advanced threat detection and response systems, are crucial to counteract the escalating danger of Chinese criminal hacking.