The U.S. Department of Justice and the FBI have seized two platforms, QScan and QTRouter, used by a China-linked group to hide cyberattacks and target critical infrastructure. The operation matters because it shows how state-backed actors no longer need to build every part of an attack from scratch: they can rely on shared scanning tools, compromised devices, commercial proxy services, and rented servers.
U.S. authorities attribute the activity to a group known as QTFY, which they say operated through the China-based company Nanjing Xinjiuwei Network Technology Company. According to the Justice Department, the group offered hacking services to paying clients that included China’s Ministry of State Security and the People’s Liberation Army.
“The Justice Department and FBI announced court-authorized domain seizures today to deny malicious cyber actors access to two complementary hacking platforms known as “QScan” and “QTRouter,” used to target U.S. critical infrastructure and other sensitive networks. As described in court documents unsealed in the Southern District of California, a People’s Republic of China (PRC) state-sponsored group known as “QTFY,” employed by China-based Nanjing Xinjiuwei Network Technology Company (南京鑫玖维网络科技有限公司), created and operated QScan and QTRouter.” reads the press release published by DoJ.
According to the Justice Department, QTFY targeted NASA, the Federal Reserve, the Departments of Energy, Justice, and Health and Human Services, the National Institutes of Health, and the U.S. Senate. Those are not random targets caught in a broad scan.
QScan and QTRouter had different jobs. QScan searched the internet for vulnerable devices and automatically infected thousands of exposed Internet of Things devices. Those compromised routers, cameras, appliances, and other connected systems were then added to QTRouter, a proxy network used to route malicious traffic through systems located outside China.
That approach makes attribution and blocking harder. A victim may see an attack coming from what appears to be a local router, a legitimate commercial proxy, or a virtual private server rented in another country. Blocking traffic by country or IP address becomes far less useful when the attacker is borrowing the identity and location of other people’s devices.
“QScan scans and automatically infects thousands of “internet-of-things” (IoT) devices worldwide, which are then added to the QTRouter network of QTFY-controlled devices. QTRouter consists of these compromised IoT devices, as well as commercial proxy service devices and leased virtual private servers.” continues DoJ. “QTRouter then serves as an “obfuscation network” – meaning it allows QTFY and other malicious cyber actors to conceal the PRC-origin of their computer intrusion activities because the malicious communications appear to originate from computers (such as those compromised by QScan) that are outside of the PRC and may even be local to the targeted networks.”
The government did not merely take down a website. The seized domains were hard-coded into QScan and QTRouter and used for core functions such as authentication and command-and-control communication. By taking control of those domains through a court order, the FBI made the malware platforms unable to operate as intended.
This is a useful example of technical disruption rather than simple attribution. Publicly naming a group matters, but it does not stop an operator who already has access to vulnerable devices and a working relay network. Taking away the infrastructure they need to manage that network is more disruptive, at least until they rebuild it.
“Because the seized domains were hard-coded into both the QScan and QTRouter malware and used for essential tasks such as communication and authentication, the court-authorized seizures made QScan and QTRouter inoperable.” DoJ states.
The broader operation looks like an industrial service model. QTFY allegedly used QScan to map targets, identify weaknesses, and compromise devices; it then used QTRouter and other proxy layers to hide where the activity actually came from. Lumen’s Black Lotus Labs described the group as a “digital quartermaster,” meaning it supplied infrastructure and services that could support multiple operations at the same time.
“To support its primary objectives, the quartermaster runs a secondary, completely decoupled target profiling utility called “QScan.” While the core proxy network focuses on managing stateful session paths, the QScan framework operates as the front-end scout.” reads a report published by Lumen. “The operations of this quartermaster demonstrate the high degree of industrialization occurring within China-nexus cyber operations. By shifting away from fragmented, ad hoc setups and toward shared multi-tenant utility networks, state-sponsored actors can execute complex campaigns with a high degree of anonymity and speed, and at a global scale.”
The group reportedly exploited both old and newly disclosed vulnerabilities in widely deployed products, including Fortinet SSL-VPN, Citrix ADC, Microsoft Exchange, F5 BIG-IP, Apache Log4j, Atlassian Confluence, Check Point gateways, CrushFTP, Ivanti appliances, and BeyondTrust Remote Support. This is not a reminder that organisations need magic detection. It is a reminder that old vulnerabilities remain useful because somebody, somewhere, will still leave them unpatched.
The attack chain also included web shells, remote-access trojans, stolen or legitimate credentials, and compromised IoT devices used as nearby relay points. That combination allows an attacker to blend into normal-looking traffic and avoids the obvious infrastructure that defenders have learned to block. A hostile connection that looks like a local consumer router is still hostile; it just has better camouflage.
This seizure follows earlier FBI actions against China-linked botnets. In 2025, the FBI removed PlugX malware from more than 4,000 infected U.S. computers linked to Mustang Panda. In 2024, it disrupted a botnet of hundreds of thousands of IoT devices associated with Flax Typhoon, while in 2023 it acted against a Volt Typhoon botnet used to conceal activity targeting U.S. and foreign critical infrastructure.
“For defenders, the operational lesson is straightforward. Inventory internet-facing assets, patch known vulnerabilities quickly, remove unsupported devices, monitor unusual outbound proxy traffic, and do not assume that an IP address tells you who is behind an attack. The same applies to IoT equipment: a router, camera, network appliance, or smart device left exposed and unmanaged can become part of someone else’s attack platform.
“This disruption announced today is among a series of court-authorized technical operations against indiscriminate hacking activities by the PRC.” concludes DoJ.
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