FBI Disrupts China-Linked QTFY Infrastructure Used to Steal Data From U.S. Organizations
FBI and Lumen disrupted QTFY's QScan and QTRouter botnet platforms used by Chinese state-sponsored hackers to conceal intrusions into U.S. agencies.
The U.S. DoJ announced court-authorized seizure of domains behind QScan and QTRouter, operated by the Chinese state-sponsored group QTFY and employed by Nanjing Xinjiuwei Network Technology Company. QTFY has been active since May 2018 and targeted NASA, the Federal Reserve, the Department of Energy, DoJ, HHS, NIH, the U.S. Senate, and academic institutions. QScan exploits vulnerable IoT devices, feeding them into QTRouter, an OpenWrt-based proxy obfuscation network likened to an operational relay box (ORB) that masks attack origins. The group exploited zero-days such as Ivanti CSA flaws CVE-2024-8190, CVE-2024-8963, and CVE-2024-9380, plus numerous N-days, and maintained persistence with RATs, web shells, and legitimate credentials.
- QScan exploits vulnerable IoT devices worldwide; QTRouter is an OpenWrt/Clash proxy network hiding Chinese attack origins.
- Targets included NASA, the Federal Reserve, DoE, DoJ, HHS, NIH, and the U.S. Senate.
- Infrastructure resembles an ORB, mixing compromised IoT devices with commercial proxy services and leased VPSes.
- Initial access leveraged Ivanti CSA zero-days and N-days in Exchange, Log4j, Confluence, F5, and others.
- Seized hard-coded domains caused both platforms to cease operations after the takedown.
Vulnerabilities mentionedAll →
| CVE | Vulnerability | CVSS | EPSS | Flags | Affected | Exposure | Published |
|---|---|---|---|---|---|---|---|
| CVE-2018-13379 | Unauthenticated Path Traversal in Fortinet FortiOS SSL VPN CVE-2018-13379 is a path traversal flaw (CWE-22) in the Fortinet FortiOS SSL VPN web portal that allows an unauthenticated attacker to download FortiOS system files via specially crafted HTTP resource requests. By traversing directories through crafted requests to the exposed web portal, the attacker can retrieve sensitive files, a technique publicly documented as yielding the SSL VPN session file containing usernames and passwords in plaintext. Any organization running the SSL VPN web portal on a FortiGate appliance is affected, and risk is highest where the portal is directly reachable from the internet. The flaw is confirmed in the wild: it was added to the CISA KEV catalog on 2021-11-03 with known ransomware use, and EPSS assigns it a 100% probability of exploitation within 30 days. No public PoC is listed in the provided data, but credential theft tied to this bug has been widely reused by threat actors. Do: Apply the patched FortiOS release per Fortinet's vendor advisory immediately, as this is a CISA KEV required action; if the fixed version is not known from this data, follow Fortinet's FG-IR-18-384 advisory for the correct upgrade path. Rotate SSL VPN credentials and review VPN access logs for path-traversal requests, since successful exploitation exposes plaintext session credentials, and restrict SSL VPN portal exposure to trusted sources where possible. | 9.8 | 100% | KEV ransomware |
| mass≈500,000 internet-exposed FortiOS SSL VPN portals (Fortinet cited ~480,000 affected devices) | |
| CVE-2019-10068 | Unauthenticated RCE in Kentico Xperience Staging Service CVE-2019-10068 is a .NET deserialization flaw (CWE-502) in the Kentico Xperience staging service that stems from a failure to validate security headers on incoming requests. Because of this, a specially crafted request can bypass the staging service's initial authentication and reach the deserialization routine with attacker-controlled .NET object data. Successful exploitation yields unauthenticated remote code execution on the server hosting the Kentico instance, with full confidentiality, integrity, and availability impact (CVSS 3.1: 9.8). All Kentico 9.x releases and 10.0.x, 11.0.x, and 12.0.x branches prior to the fixed builds (10.0.52, 11.0.48, 12.0.15) are affected. Exploitation is confirmed: the flaw is in CISA's Known Exploited Vulnerabilities catalog (added 2022-03-25), carries a very high EPSS score of 95.1%, and a public proof-of-concept for Kentico CMS 12.0.14 remote command execution is available. Do: Upgrade affected instances immediately: 12.x to 12.0.15 or later, 11.x to 11.0.48 or later, and 10.x to 10.0.52 or later; for 9.x, apply the vendor-provided patch per Kentico's update instructions. Until patched, restrict access to the staging service (limit it to trusted internal networks/synchronization peers) and review logs for unauthenticated or anomalous requests to the staging endpoint. | 9.8 | 95% | KEV PoC |
| large≈tens of thousands of deployments (commercial enterprise CMS, commonly tens of thousands of licensed sites, with the staging service often internet-reachable) | |
| CVE-2019-19781 | Unauthenticated path traversal RCE in Citrix ADC, Gateway, and SD-WAN WANOP CVE-2019-19781 is a path-traversal flaw (classified CWE-22, though CISA's description calls it unspecified) in Citrix ADC (formerly NetScaler ADC), Citrix Gateway, and Citrix SD-WAN WANOP appliances that lets an unauthenticated remote attacker traverse directories via crafted requests and execute arbitrary commands on the appliance, typically with root privileges. It is triggered by sending specially crafted directory-traversal requests (crafted URLs/requests to the appliance's management or VPN endpoints), which lets the attacker write files and run commands with no credentials. Successful exploitation yields arbitrary code execution on the appliance, enabling theft of VPN/ADC credentials, lateral movement into the corporate network, and installation of persistent backdoors. Any organization running affected ADC, Gateway, or SD-WAN WANOP firmware is affected, with internet-facing gateways used for remote access at the highest risk. Exploitation is confirmed in the wild: the vulnerability is on CISA's KEV (added 2021-11-03) with known ransomware use, EPSS assigns near-certain (100.0%) probability of exploitation within 30 days, and no public PoC is listed despite confirmed abuse. Do: Upgrade Citrix ADC, Gateway, and SD-WAN WANOP appliances to the fixed firmware builds listed in Citrix advisory CTX267020; if patching cannot be done immediately, apply Citrix's published interim mitigation and restrict internet exposure to the appliance. Because exploitation grants root code execution and persistence, after patching hunt for indicators of compromise (unexpected nsroot account, modified system files, crontab/scheduled entries), kill all active and inactive sessions, and rotate appliance and VPN credentials. Prioritize internet-facing gateways and comply with CISA's required action to apply vendor updates. | 9.8 | 100% | KEV ransomware |
| massroughly 80,000-100,000+ internet-exposed Citrix ADC/Gateway appliances at the time of disclosure, with a far larger total installed base (including… | |
| CVE-2020-5902 | Unauthenticated RCE via path traversal in F5 BIG-IP TMUI CVE-2020-5902 is a critical, unauthenticated remote code execution flaw in the F5 BIG-IP Traffic Management User Interface (TMUI), the appliance's web management console, rooted in a directory/path traversal issue (CWE-22) in undisclosed TMUI pages. It is triggered by sending crafted HTTP(S) requests to the management interface — classically path-traversal URLs beneath the TMUI application on the management port — which lets an attacker bypass authentication, read or delete arbitrary files, and execute commands without credentials. Successful exploitation yields full control of the BIG-IP system, which attackers can use to pivot into networks the appliance fronts, maintain persistence, and deploy ransomware. Any organization running an affected F5 BIG-IP appliance or virtual edition whose TMUI is reachable, or whose management network can be reached, is exposed; F5's installed base spans large enterprises and service providers, so the footprint is broad. Exploitation is confirmed in the wild: the flaw was mass-scanned and exploited within days of its July 2020 disclosure, it is listed in CISA KEV with known ransomware use, and EPSS assigns a ~100% probability of exploitation within 30 days. Do: Patch immediately using F5's advisory K52145254 — upgrade BIG-IP to a fixed release per the vendor's version matrix, since CISA's required action is applying vendor updates. Until patched, restrict TMUI/management-interface access to trusted source IPs or a VPN (or disable TMUI if unused) and apply F5's published interim workaround. Because ransomware use is confirmed, hunt for indicators of compromise on both patched and unpatched appliances (unexpected files, webshells, modified login pages, new accounts or scheduled tasks) before treating systems as clean. | 9.8 | 100% | KEV ransomware PoC ×8 |
| mass≈100,000–300,000 internet-exposed BIG-IP TMUI endpoints, with a far larger internal installed base | |
| CVE-2021-26855 | Unauthenticated SSRF/RCE in Microsoft Exchange Server (ProxyLogon) CVE-2021-26855 is a server-side request forgery flaw (CWE-918) in Microsoft Exchange Server that allows an unauthenticated remote attacker to send specially crafted HTTP requests and have the Exchange server process them as itself, disclosing sensitive session information. When chained with sibling Exchange flaws (the 'ProxyLogon' chain), it yields authentication bypass and arbitrary file write, escalating to full remote code execution with SYSTEM-level privileges on the on-premises Exchange server. Any organization running an affected on-premises Exchange server reachable over HTTP/HTTPS (typically outbound webmail) is exposed; Exchange Online was not affected. Exploitation is confirmed in the wild at large scale: the flaw was mass-exploited beginning in early 2021 (notably by the HAFNIUM group), is on the CISA KEV with documented ransomware use, and has a maximum EPSS score of 100% (100th percentile), despite no public PoC listing. Do: Apply the vendor's March 2021 Exchange security updates (or later cumulative updates) immediately, per the CISA required action; until patched, limit Exchange (ECP/OWA) exposure to the internet via firewall/VPN rules. Hunt for compromise: review IIS logs for unrecognized authenticated activity against FrontEnd HttpProxy endpoints, and check for malicious files or webshells under inetpub\wwwroot\aspnet_client, given the known ransomware use. | 9.1 | 100% | KEV ransomware PoC ×4 |
| masshundreds of thousands of on-premises deployments; tens of thousands of internet-exposed Exchange servers | |
| CVE-2021-44228 | JNDI Injection Remote Code Execution in Apache Log4j2 (Log4Shell) Apache Log4j2, an extremely widely used Java logging library, fails to protect its JNDI lookup feature against attacker-controlled JNDI-related endpoints (CWE-20, CWE-502), so crafted text processed by the logger causes the Java runtime to fetch and load attacker-supplied objects, leading to remote code execution. The flaw is triggered whenever attacker-controlled input reaches the logging API and is parsed for JNDI lookups, a pattern common in web servers and enterprise Java applications that log user-supplied fields such as headers or form values. Successful exploitation yields arbitrary code execution under the privileges of the affected application, giving attackers a foothold for lateral movement, data theft, and ransomware deployment. Any Java application or product that ships or bundles an affected Apache Log4j2 release is exposed, making this one of the most broadly deployed vulnerabilities ever disclosed. Exploitation is confirmed in the wild: CISA added it to the Known Exploited Vulnerabilities catalog on 2021-12-10 with known ransomware use, and EPSS assigns a 100% probability of exploitation within 30 days. Do: Inventory all Java applications and dependencies for Apache Log4j2 and apply the vendor's patched updates, or remove affected assets from the network, as required by CISA's KEV catalog. Where updates are not yet available, use the temporary mitigations in CISA's ED-22-02 recommended-mitigation guidance, such as disabling message lookups, only until patches are applied. Prioritize internet-facing and business-critical systems and hunt for exploitation activity given known ransomware use. | 10.0 | 100% | KEV ransomware PoC ×9 |
| masshundreds of millions of Java applications/devices, with hundreds of thousands of internet-exposed services | |
| CVE-2023-22515 | Unauthenticated Broken Access Control in Atlassian Confluence Data Center/Server Atlassian Confluence Data Center and Server contain a broken access control flaw (CWE-20) in publicly accessible instances that allows unauthenticated remote attackers to create unauthorized Confluence administrator accounts and gain access to the instance; the associated public PoC is titled 'Atlassian Confluence Unauthenticated Remote Code Execution'. The flaw is triggered over the network (CVSS 3.1 9.8, AV:N/AC:L/PR:N/UI:N) against any self-managed Confluence instance reachable from the internet, with no privileges or user interaction required. Attackers who exploit it gain administrator-level control of the Confluence instance, and the public PoC demonstrates this extends to unauthenticated code execution. Only self-managed Confluence Data Center and Server deployments are affected; Atlassian Cloud sites hosted on atlassian.net domains are not vulnerable. Exploitation is confirmed in the wild: CISA added it to the KEV on 2023-10-05 with known ransomware use, EPSS is 99.2%, Atlassian reported a handful of customers were already exploited, and Microsoft warned of nation-state (China-linked) abuse. Do: Patch all internet-facing Confluence Data Center and Server instances to a fixed release per Atlassian's advisory (specific fixed versions are not listed in this data), or restrict public access/discontinue use per CISA's required action. Audit every affected instance for evidence of compromise, especially unauthorized administrator accounts created through this flaw, and report positive findings to CISA. Treat this as urgent given active exploitation by both nation-state actors and ransomware groups. | 9.8 | 99% | KEV ransomware PoC |
| large≈ tens of thousands of internet-exposed Confluence Data Center/Server instances (order of ~30,000-50,000) | |
| CVE-2024-24919 | Information Disclosure in Internet-Facing Check Point Quantum Security Gateways Check Point Quantum Security Gateways contain an information disclosure flaw (CWE-200) that can expose information stored on the appliance to unauthorized parties. It is triggered when an attacker targets a gateway connected to the internet with IPSec VPN, Remote Access VPN, or Mobile Access enabled, sending crafted requests to the exposed VPN services. A successful attacker gains unauthorized access to information on the gateway, and CISA notes known use of this flaw in ransomware campaigns. The issue spans multiple Check Point product lines: CloudGuard Network, Quantum Scalable Chassis, Quantum Security Gateways, and Quantum Spark Appliances. Exploitation is confirmed in the wild: the flaw was added to CISA's KEV catalog on 2024-05-30 with ransomware use listed, and EPSS assigns a 100% probability of exploitation within 30 days, though no public proof-of-concept is known. Do: Apply the hotfix Check Point distributes per its advisory (SK170863) to all internet-facing gateways running IPSec VPN, Remote Access VPN, or Mobile Access; this is also the CISA KEV required action. Where the hotfix cannot be applied immediately, restrict or disable the Remote Access VPN and Mobile Access software blades as an interim mitigation. Review gateway and VPN logs for signs of exploitation and prioritize remediation given confirmed ransomware use. | 8.6 | 100% | KEV ransomware |
| largetens of thousands of internet-exposed VPN gateways (10k-100k systems) | |
| CVE-2024-8190 | OS Command Injection RCE in Ivanti Cloud Services Appliance 4.6 Ivanti Cloud Services Appliance versions 4.6 Patch 518 and before contain an OS command injection flaw (CWE-78) that allows a remote, authenticated attacker to achieve remote code execution. The attacker must already hold administrator-level privileges on the appliance, and exploitation is triggered by sending crafted input to the appliance over the network. Successful exploitation yields arbitrary command execution on the CSA, and related reporting indicates nation-state actors have been exploiting Ivanti CSA flaws for network infiltration, including attacks on French government and telecom targets. Only organizations still running CSA 4.6.x are affected, and that product line has reached end-of-life and will not receive further security updates. The vulnerability was added to CISA's Known Exploited Vulnerabilities catalog on 2024-09-13 and carries a very high EPSS score (88.5%, 100th percentile), signaling confirmed and likely ongoing exploitation in the wild. Do: Because CSA 4.6.x has reached end-of-life, remove CSA 4.6.x from service or migrate to the supported 5.0.x line, as future 4.6.x flaws are unlikely to receive fixes. Given confirmed nation-state exploitation, hunt for signs of compromise such as unexpected admin sessions, processes, or network tunnels, and restrict internet exposure of any remaining 4.6.x appliances in the interim. | 7.2 | 89% | KEV |
| moderateroughly 1,000–2,000 internet-exposed CSA appliances (public internet scan counts) | |
| CVE-2024-8963 | Unauthenticated Path Traversal in Ivanti Cloud Services Appliance CVE-2024-8963 is a path traversal vulnerability (CWE-22) in the Ivanti Cloud Services Appliance (CSA), a virtual appliance used to remotely manage Ivanti Endpoint Manager environments. A remote, unauthenticated attacker can send crafted requests containing directory traversal sequences to reach restricted functionality without any credentials. Successful exploitation grants access to restricted (including administrative) functions on the appliance, and public reporting indicates it has been chained with other CSA zero-day flaws by nation-state attackers to infiltrate networks. All CSA 4.6.x releases before Patch 519 are affected, and the 4.6.x product line has reached end-of-life, meaning future 4.6.x vulnerabilities will not receive fixes. Exploitation is confirmed in the wild: CISA added it to the Known Exploited Vulnerabilities catalog on 2024-09-19, and multiple outlets report Chinese-linked actors exploiting CSA zero-days against French government, telecom and other critical-infrastructure targets. Do: Upgrade CSA 4.6.x to Patch 519 or later, or move to the supported 5.0.x line; because 4.6.x is end-of-life, CISA urges removing CSA 4.6.x from service or migrating to 5.0.x rather than relying on future 4.6.x patches. Until patched, restrict or remove internet exposure of CSA appliances and review logs for unauthenticated access to restricted functionality, since this flaw is being chained with other CSA vulnerabilities in targeted intrusions. | 9.1 | 99% | KEV |
| moderate≈1,000–2,000 internet-exposed CSA appliances (order of magnitude; installed base larger if internal-only deployments are counted) | |
| CVE-2024-9380 | OS Command Injection RCE in Ivanti Cloud Services Appliance Admin Console CVE-2024-9380 is an OS command injection flaw (CWE-77/CWE-78) in the admin web console of Ivanti Cloud Services Appliance (CSA), fixed in version 5.0.2. A remote attacker who is already authenticated with administrative privileges can inject arbitrary operating system commands through the console, which the appliance then executes. Successful exploitation yields remote code execution with high impact on confidentiality, integrity, and availability (CVSS 3.1: 7.2). All CSA releases before 5.0.2 are affected, and the widely deployed 4.6.x line has reached End-of-Life, so EOL users must remove it from service or move to 5.0.x or later. The flaw was added to CISA's Known Exploited Vulnerabilities catalog on 2024-10-09, and contemporaneous reporting describes Chinese nation-state actors exploiting Ivanti CSA zero-days against French government and telecom targets, with a 63.2% EPSS probability of exploitation in the next 30 days (99th percentile). Do: Upgrade Ivanti CSA to 5.0.2 or later; if you are running the End-of-Life 4.6.x line, either remove it from service or migrate to the supported 5.0.x line, per CISA's KEV required action. Restrict exposure of the admin web console (do not leave it directly internet-facing) and verify whether your appliance was targeted. Given reported nation-state exploitation of CSA zero-days, review appliance logs and admin credentials for signs of compromise. | 7.2 | 63% | KEV |
| moderate≈ a few thousand internet-exposed CSA appliances; total installed base likely in the low tens of thousands | |
| CVE-2025-31161 | Authentication Bypass in CrushFTP File Transfer Servers (CVE-2025-31161) CrushFTP contains an authentication bypass (CWE-305) in its handling of the HTTP authorization header, allowing crafted header values to grant access without valid credentials. A remote, unauthenticated attacker who can reach the server's HTTP/HTTPS interface can use this flaw to authenticate as any known or guessable account, such as the built-in crushadmin user. With administrative access, the attacker can typically achieve full compromise of the file-transfer server, including access to hosted files and user accounts. Any organization running CrushFTP is affected, with internet-exposed instances at the highest risk. The flaw is being actively exploited: it was added to CISA's KEV on 2025-04-07 with known ransomware use, and EPSS assigns it a 100% probability of exploitation within 30 days. Do: Upgrade to the vendor's fixed releases (10.8.0 for the 10.x line and 11.3.1 for the 11.x line, per vendor advisories); federal agencies must follow BOD 22-01 timelines or discontinue use if mitigations are unavailable. Until patched, restrict network access to the CrushFTP HTTP/HTTPS interface and audit authentication logs for unexpected logins to privileged accounts such as crushadmin. Given confirmed ransomware use, treat internet-exposed instances as actively targeted and verify there are no signs of prior compromise after patching. | 9.8 | 100% | KEV ransomware PoC ×4 |
| moderate≈5,000–10,000 internet-exposed CrushFTP servers (public scan counts), with additional uncounted internal enterprise deployments | |
| CVE-2026-1731 | Pre-Authentication OS Command Injection RCE in BeyondTrust Remote Support and PRA BeyondTrust Remote Support (RS) and certain older versions of Privileged Remote Access (PRA) contain a critical (CVSS 4.0: 9.9) pre-authentication operating system command injection vulnerability (CWE-78). By sending specially crafted requests to the appliance, an unauthenticated remote attacker can execute operating system commands in the context of the site user, gaining code execution without credentials or user interaction. Any organization running RS or PRA appliances that are reachable from the internet, which is their typical deployment mode for remote support and privileged access, is affected. Exploitation is active: the flaw was added to CISA's Known Exploited Vulnerabilities catalog on 2026-02-13 with known ransomware use, carries an EPSS of 89.5% (100th percentile), has a public proof-of-concept, and press coverage links the newly patched BeyondTrust RCE to fast-moving ransomware activity (Storm-1175). BeyondTrust has released fixes, so unpatched, internet-exposed instances should be treated as high-priority compromise targets. Do: Upgrade all internet-exposed Remote Support and Privileged Remote Access appliances to the fixed releases in BeyondTrust's security advisory immediately, per the CISA KEV required action (apply vendor mitigations or discontinue use if mitigation is unavailable). Until patched, restrict network access to the appliance and review appliance/web logs for suspicious unauthenticated requests, given known ransomware exploitation and the availability of a public proof-of-concept. | 9.9 | 90% | KEV ransomware PoC |
| largeon the order of tens of thousands of internet-exposed RS/PRA appliance instances worldwide |
Full article1,062 words · extracted from thehackernews.com · click to collapse
The U.S. Department of Justice (DoJ) on Wednesday announced the disruption of two hacking platforms named QScan and QTRouter operated by Chinese threat actors to target critical infrastructure and other sensitive networks in the country.
The activity has been attributed to a Chinese state-sponsored group known as QTFY, employed by Nanjing Xinjiuwei Network Technology Company (南京鑫玖维网络科技有限公司).
"Among the targets of QTFY are the National Aeronautics and Space Administration, Federal Reserve, Department of Energy, Department of Justice, Department of Health and Human Services, National Institutes of Health, and the U.S. Senate," DoJ said.
Damon Rouse, a security researcher at Lumen Black Lotus Labs who has been tracking the activity for over the past 18 months, told The Hacker News that the digital quartermaster has been active since May 2018. Nanjing counts both China's Ministry of State Security (MSS) and the People's Liberation Army (PLA) among its customers.
Lumen said it began collaborating with the U.S. Federal Bureau of Investigation (FBI) on QTFY about a year ago. "The targeting was throughout the western world and beyond, especially with regard to academia," the company added. "They just love hitting research communities given the collaborative nature of advanced science."
"Today we announced the disruption of a global botnet and hacking platform used by Chinese state-sponsored hackers to target U.S. critical infrastructure," said FBI Director Kash Patel. "These tools were used by PRC cyber actors to hide the origin of their attacks."
Two of the prominent tools are QScan, which scans and automatically infects IoT devices worldwide, and then adds them to the QTRouter network. QTRouter comprises both the compromised devices and commercial proxy service devices and leased virtual private servers (VPSs).
QTRouter effectively serves as an obfuscation network that allows QTFY and other Chinese cyber actors to conceal the true origins of their computer intrusion activities, giving the impression that the communications are coming from endpoints that are geolocated outside China and possibly local to the targeted networks.
QScan has been associated with a number of domains that host different components of the system -
- qt-proxy[.]org
- mq-task.qt-proxy[.]org (previously, mq-task.qt-team[.]com), which provides scanning tasks to a pool of worker nodes primarily housed on leased servers located outside of China
- mq-result.qt-proxy[.]org (previously, mq-result.qt-team[.]com), which receives completed tasks
"QScan is used to exploit vulnerable IoT devices and identify vulnerabilities in victim networks. QTFY uses botnet products to control the compromised IoT devices and include them as QTRouter proxy nodes," the FBI said. "This enables QTFY-affiliated actors to blend in with legitimate users when targeting victim organizations."
QTRouter, which functions as a network traffic obfuscation network running on routers with custom OpenWrt software, authenticates to administration servers located at "www.qtproxy[.]xyz" and "securelink.qtproxy[.]xyz."
"QTRouter uses Clash to establish proxy connections," the FBI explained. "Its functionality includes viewing available nodes and chaining nodes together to obfuscate the actor behind the malicious activity. Additionally, by mixing the malicious traffic with legitimate traffic on commercial proxy services and using compromised IoT devices to utilize the locations of legitimate users, QTRouter makes it difficult to identify and track the malicious activity."
The botnets of hacked devices are commandeered using three major platforms: Proxy Platform Management, Proxy Pool Management System, and QTBotnet, the last of which includes a controller server, secondary-level control servers to maintain communication between the main control server and compromised devices, and compromised devices. The control server is also equipped to launch DDoS attacks and run commands on infected nodes.
The entire attack cycle is as follows -
- Use QScan to conduct reconnaissance against victim networks
- Exploit zero-day (e.g., CVE-2024-8190, CVE-2024-8963, and CVE-2024-9380 in Ivanti CSA appliances) and N-day vulnerabilities (CVE-2018-13379 in Fortinet SSL-VPN, CVE-2019-19781 in Citrix ADC, CVE-2021-26855 in Microsoft Exchange Server, CVE-2020-5902 in F5 BIG-IP, CVE-2019-10068 in Kentico CMS, CVE-2021-44228 in Apache Log4j, CVE-2023-22515 in Atlassian Confluence, CVE-2024-24919 in Check Point Quantum Gateway, CVE-2025-31161 in CrushFTP, and CVE-2026-1731 in BeyondTrust Remote Support) to gain initial access to victim networks
- Establish persistence using remote access trojans (RAT), web shells, and legitimate credentials
- Use QTRouter to accès the victim network from nearby compromised IoT to fly under the radar
The seized domains are said to have been hard-coded into both products, causing them to cease operations following the court-authorized action.
The distributed architecture is a set of interconnected components that includes QScan, QTRouter, and two others, per Lumen -
- Fast Labyrinth, which provides the operational layer by incorporating commercial proxy infrastructure such as Fastlink ("fastlink.ws") into an encrypted relay network along with QTRouter that obfuscates traffic to and from target entities
- QTProxy, which manages Fast Labyrinth operational nodes and allows operators to use preconfigured relays or configure unique paths to target entities
The infrastructure has been likened to an operational relay box (ORB), a decentralized mesh that comprises infected IoT devices and leased VPSs and allows malicious traffic to be routed through rotating IPs and evade traditional defenses like IP blocklists and location-based policies.
"Since its establishment in 2018, the China-linked hacking group QTFY has developed malicious tooling, traded malware and exploits within freelance hacking networks, established and maintained an obfuscation botnet, and ultimately targeted critical systems in the United States," the FBI said.
The agency described Nanjing as an enabling company that has business relationships with larger private China-based cyber-enabling companies with expertise in critical infrastructure security to target victim organizations. It also encompasses former PLA members and takes advantage of their contacts to land contracts related to critical infrastructure targeting.
What's more, QTFY actors are alleged to have participated in China-based freelance brokering networks to acquire and sell cyber exploit items, including access to victim networks. Attacks as recent as June 2026 have targeted a U.S. election system.
"The operations of this quartermaster demonstrate the high degree of industrialization occurring within China-nexus cyber operations," Lumen said. "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."
"Because these transit loops are procured via legitimate paid subscriptions to commercial proxy services, traditional static blocks are no longer sufficient to stop the threat."
(The story was updated after publication on September 2, 2026, to reflect a correction issued by the U.S. Justice Department. Please check here for more details.)
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Text extracted automatically; images, tables and formatting may be missing. Original: https://thehackernews.com/2026/08/fbi-disrupts-china-linked-qtfy.html