JDY Botnet: The Silent "Eye" Behind China's Cyber Attack Campaigns
Campaign summary
In June 2026, Lumen Black Lotus Labs confirmed that after the KV-botnet cluster was busted by the FBI in early 2024, the remaining JDY cluster did not disband — it quietly restructured and has now expanded to more than 1,500 hijacked SOHO and IoT devices, doubling from the bottom of ~650 devices after the takedown. This botnet is linked to Chinese APT groups, including Volt Typhoon, and acts as a large-scale reconnaissance system: scanning services, fingerprinting infrastructure, and transferring data back to serve the next exploits.
The most worrying point is not so much the scale — but the speed of response: just hours after the Fortinet vulnerability CVE-2026-35616 was announced on April 5, 2026, JDY began mass scanning to identify unpatched devices. Of all the IPs targeted, the largest group belonged to US military networks and related entities — no coincidence.
Some information about Volt Typhoon
Introduce
Volt Typhoon is an Advanced Persistent Threat (APT) group that has been tracked for many years by Western intelligence and cybersecurity agencies, including Microsoft, CISA, NSA and FBI. This group is believed to be linked to the Chinese state and operates with the goal of gathering strategic intelligence and building long-term access to critical infrastructure systems.
Unlike many APT groups that focus on data theft or economic espionage, Volt Typhoon is considered to target national security and military strategies. The group's campaigns often target organizations that play an important role in social operations and defense, suggesting that the goal is not only to collect information but also to prepare the ability to impact or disrupt infrastructure in crisis situations.
Activity history
Signs of Volt Typhoon's activity were traced back to around 2021, but the group only became widely publicized in May 2023 when Microsoft published a report on a large-scale intrusion campaign targeting critical US infrastructure.
In early 2024, the FBI and the US Department of Justice conducted a campaign to destroy the KV Botnet infrastructure - the proxy network used by Volt Typhoon to hide the origin of the attack. However, subsequent studies showed that many other infrastructure components such as the JDY Botnet continued to operate and even expanded significantly.
Strategic goals
Critical infrastructure: Electricity, Energy, Clean Water, Gas, Telecommunications, Transportation.
Defense: Ministry of Defense, Military Contractors, Military Logistics Facilities, Force Deployment Support Systems.
Government: Administrative agencies, Strategic Research Organizations, National Infrastructure Management Agency.
Technology and Telecommunications: ISPs, Internet Service Providers, Data Centers, Network Management Systems.
Event Timeline
| Date | Event |
|---|---|
| December 2023 | Lumen Black Lotus Labs publicly disclosed the KV Botnet, consisting of two distinct components: the KV cluster, responsible for covert traffic relaying and proxy operations, and the JDY cluster, dedicated to large-scale reconnaissance and Internet scanning. The infrastructure was linked to activities associated with Volt Typhoon targeting U.S. critical infrastructure. |
| January 2024 | The FBI and U.S. Department of Justice conducted a court-authorized disruption operation against the KV cluster. Following the takedown, the JDY cluster remained active but dropped to its lowest observed size of approximately 650 compromised devices. |
| January–December 2024 | JDY quietly rebuilt its infrastructure and expanded its operational footprint. The botnet broadened its targeting scope beyond Cisco RV320/RV325 routers, incorporating a wider range of SOHO and edge devices from multiple vendors. |
| Q1–Q2 2026 | JDY grew to more than 1,500 compromised devices globally. Researchers observed increased targeting of products from Araknis Networks, Mimosa Networks, Ubiquiti, DrayTek, Hikvision, and Linksys, demonstrating a significant diversification of its victim ecosystem. |
| April 5, 2026 | CVE-2026-35616, a critical vulnerability affecting Fortinet products, was publicly disclosed. Black Lotus Labs observed JDY initiating reconnaissance and scanning activity against potentially vulnerable Fortinet devices on the same day, highlighting its rapid response capability to newly published vulnerabilities. |
| June 10, 2026 | Lumen Black Lotus Labs released a comprehensive technical report detailing JDY’s infrastructure, malware functionality, command-and-control architecture, reconnaissance techniques, and targeting patterns. |
| June 11, 2026 | Major cybersecurity media outlets, including The Hacker News and Security Affairs, published analyses covering JDY’s expansion, its relationship to Volt Typhoon, and its role in large-scale vulnerability reconnaissance operations. |
Chain attack
DY is not a direct attack botnet — it is a specialized reconnaissance layer serving downstream exploitation. Each stage is designed to maximize the data collected while minimizing the footprint left behind.
Three technical points are especially worth noting:
Self-deleting dropper: After downloading and launching the payload, the dropper automatically deletes the binary. There's nothing to be found after the malware has run.
Detection rule on demand: When receiving commands from C2, JDY downloads custom detection signatures — not blind scanning, but identifying and validating specific services by behavioral characteristics, port, and response pattern.
Geofencing bypass by design: By dispersing scanning across thousands of IPs belonging to legitimate US SOHO/IoT networks, the botnet naturally bypasses IP reputation blacklists, geofencing rules, and static blocklists — because the traffic looks exactly like real users.
Technical details
Overall architecture
Analysis by Black Lotus Labs shows that JDY does not operate as a traditional DDoS botnet but is designed as a distributed network reconnaissance platform (Distributed Reconnaissance Platform).
JDY's architecture includes three main components:
Bot Layer
The bot class includes compromised SOHO and IoT devices:Router
Firewall
VPN Gateway
Camera IP
NAS devices
Small business network equipment
After being hijacked, these devices become distributed scanner nodes on the Internet.
Command and Control Layer
The C2 system uses multiple layers of intermediaries to reduce the risk of takedown.Outstanding features:
Communicate over HTTPS
JSON-based protocol
Tor Hidden Services
Infrastructure is distributed across many geographical areas
Using Tor helps hide the physical location of the control server and makes sinkhole or takedown operations difficult.
Aggregation & Analytics Layer
This is the most important component of JDY.All data collected from thousands of bots will be centralized at central analytics servers to:
Merge scan data
Eliminate duplicate data
Build inventory of Internet-facing assets
Identify systems vulnerable to exploitation
The final results are passed on to mining campaigns or related APT groups.
Operational process
Stage 1: Initial Registration
After successful infection, the bot sends identification information to C2.
Information includes:
| Data Field | Purpose |
|---|---|
| OS Type | Identify the operating system running on the compromised device |
| Architecture | Determine the CPU architecture (e.g., x86, x64, ARM, MIPS) |
| Uptime | Assess device stability and operational reliability |
| Memory Size | Evaluate available system resources and execution capacity |
| Malware Version | Track and manage bot malware versions deployed across the botnet |
| Public IP Address | Determine the device's external network location and geographic distribution |
Việc thu thập các thông tin này giúp hệ thống lựa chọn nhiệm vụ phù hợp với từng bot.
Giai đoạn 2: Task Distribution
Sau khi đăng ký thành công, bot nhận nhiệm vụ từ C2.
Một scan task thường bao gồm:
{
"targets": [
"203.0.113.0/24",
"198.51.100.0/24"
],
"ports": [80,443,8443],
"protocols": ["HTTP","HTTPS"],
"fingerprinting": true,
"tls_collection": true
}
Tasks can be continuously updated based on:
Newly announced CVE
APT campaign is underway
List of priority goals
Network scanning techniques
SYN Scan
If the bot has permission to use the raw socket, JDY performs a SYN Scan similar to Nmap.
Advantages:
TCP handshake not completed
Reduced log generation on target device
Increase scanning speed
This helps JDY maintain a higher level of stealth than conventional scanning tools.
TCP Connect Scan
When raw sockets cannot be used:
This method creates more footprint but ensures limited compatibility with IoT devices.
Banner Grabbing
After determining the open port, JDY conducts fingerprinting.
For example:
HTTP/1.1 200 OK
Server: nginx/1.18.0
X-Powered-By: PHP/7.4
Information collected:
Web Server
Version
Framework
Reverse Proxy
CDN Information
Application Stack
These data are used to determine the likelihood that known vulnerabilities exist.
TLS Fingerprinting
One of JDY's standout capabilities is TLS data collection.
Information collected includes:
| Attribute | Purpose |
|---|---|
| TLS Version | Identify the security configuration and supported TLS protocol version |
| Cipher Suite | Fingerprint and classify devices, applications, or services |
| Certificate Subject | Identify the organization, domain, or service associated with the certificate |
| Subject Alternative Name (SAN) | Enumerate hostnames and additional domains covered by the certificate |
| Certificate Issuer | Determine the Certificate Authority (CA) that issued the certificate |
| Expiration Date | Assess certificate validity status and expiration timeline |
For example:
TLS 1.2
CN=vpn.company.com
Issuer=DigiCert
Through digital certificates, JDY can identify:
Internal domain name
VPN system
Remote access port
Administration equipment
HTTP Redirect Analysis
JDY not only collects banners but also tracks redirect chains.
For example:
http://target
↓
https://vpn.company.com
↓
Fortinet SSL VPN Portal
This information helps:
Identify security devices
Product classification
Identify the VPN system
Target classification
After data is sent to the central server, the system conducts classification.
Step 1: Asset Classification
Determine:
Firewall
Router
VPN Gateway
Camera
NAS
ICS Device
Step 2: Product Fingerprinting
For example:
FortiGate
Cisco IOS XE
DrayTek Vigor
Hikvision Camera
Step 3: Vulnerability Matching
Collation system:
Product Version
↓
Known CVEs
↓
Risk Score
Devices with potential vulnerabilities will be placed on the priority list.
Technical review
JDY is a highly automated reconnaissance-as-a-service platform designed to shorten the time between vulnerability disclosure and target discovery. Unlike traditional DDoS botnets, JDY's value lies in its ability to build a real-time Internet-facing assets database, supporting large-scale cyber espionage and exploitation campaigns. With over 1,500 controlled devices and in-depth TLS data collection, banner and fingerprinting capabilities, JDY is currently considered one of the most notable cyber reconnaissance platforms involved in APT activities originating from China.Thiết bị nhắm đến
Vendors/Models confirmed to be infected or targeted by JDY:
Cisco RV320, RV325
Ubiquiti UniFi series
Draytek Vigor series
Hikvision IP cameras / NVR
Linksys WRT/EA series
Araknis Networks AN series
Mimosa Networks wireless equipment
Vulnerabilities Exploited/Targeted
CVE-2026-35616 # Fortinet — scanned on public disclosure day (April 5, 2026)
MITRE ATT&CK Mapping
| Phase | Technique ID | Technique Name | JDY Activity Description |
|---|---|---|---|
| Reconnaissance | T1595 | Active Scanning | Conducts large-scale SYN scanning and TLS fingerprinting across Internet-facing systems |
| Reconnaissance | T1595.001 | Scanning IP Blocks | Scans IP ranges associated with U.S. military, government, and critical infrastructure networks |
| Reconnaissance | T1590 | Gather Victim Network Information | Collects service banners, SSL/TLS certificates, and protocol metadata from exposed services |
| Reconnaissance | T1590.004 | Gather Victim Network Information: Network Topology | Maps exposed services and network infrastructure to support downstream exploitation activities |
| Resource Development | T1584.005 | Compromise Infrastructure: Botnet | Compromises SOHO and IoT devices to build a distributed reconnaissance and proxy network |
| Command and Control | T1090.003 | Proxy: Multi-hop Proxy | Utilizes Tor hidden services and intermediary nodes to conceal C2 infrastructure |
| Command and Control | T1071.001 | Application Layer Protocol: Web Protocols | Uses HTTPS-based communications for bot registration, tasking, and result submission |
| Defense Evasion | T1070.004 | Indicator Removal on Host: File Deletion | Dropper components may remove themselves after execution to reduce forensic artifacts |
| Defense Evasion | T1036 | Masquerading | Blends reconnaissance traffic with legitimate SOHO and residential network traffic patterns |
| Defense Evasion | T1562.001 | Impair Defenses: Disable or Modify Security Tools | Evades IP reputation systems and geofencing controls by leveraging compromised U.S.-based SOHO devices as scanning nodes |
IOC
IP C2
23.27.120[.]240
109.104.154[.]116
216.173.65[.]250
194.14.217[.]88
149.248.3[.]38
SHA 256
2b640582bbbffe58c4efb8ab5a0412e95130e70a587fd1e194fbcd4b33d432cf
03c4667f016f1e8441177639d87f77a59f32d2c7e0041616376967338667bd3b
1e0da906811b570c4134ade310c3a94631d4b308d27b616497266b49aae2aa
d62055910cd579ff1fb57bd1926c5b2e80e1677f0316737b2f733f86b01615dc
40ad28b87b5ed395fe8ff303555cc28974682ed6cc5a71ede76c4b17648cbd
28a23ab78739de674f94d9acadfe0709862c2b2d947e9051b200a24d3f9f44
d1414803a83b1ba260e3e1be742379eccbb806f987ec1e7c0bc5399e4971a5f
96ecc107aa645e36b5f939ebfcf9e61fc9ebc27616680fbd0fdeb41c7950d79a
Expert Comments
Takedown Is Not the End — Resilience By Design
The FBI takedown of KV-botnet in early 2024 is considered successful. But JDY's story proves that disruption of a cluster does not eliminate capability. Volt Typhoon (or related threat actor) designed the KV-botnet with a distributed architecture: when the KV cluster is taken down, the JDY cluster remains alive and continues to accumulate.
This is not the first time we have seen this pattern. Emotet, TrickBot, Qakbot — all show that botnets are capable of regenerating after disruption when the infrastructure is not completely taken down. The difference with JDY is patience: it doesn't rush, doesn't make noise, just quietly collects for 2 years.
Reconnaissance-First: Paradigm Changes In APT Operations
Traditionally, we think of APT = intrusion → lateral movement → exfiltration. JDY raises another question: if you have a detailed map of all your competitors' exposed services — updated continuously, daily — how quick is the "initial access" step?
CVE-2026-35616 case study answers that question: within hours of disclosure, JDY knew exactly which organizations were unpatched. When the exploit tool is ready, the target list has been prepared. This is assembly-line exploitation — industrialized, not opportunistic.
Risks for Vietnam and ASEAN
Although current targeting prioritizes US military networks, the analyst team sees some notable signals for the region:
Geographic distribution of bots includes Asia: this means that SOHO/IoT in Vietnam and ASEAN countries may already be in a botnet, not the main target but a tool used to attack others.
Popular devices in Vietnam: Hikvision IP cameras, Linksys routers — are all on the list targeted by JDY. The possibility of infection in Vietnam is real, not theoretical.
Precedent from Volt Typhoon: This group has a history of targeting critical infrastructure. If the pattern expands to ASEAN — especially in the current geopolitical context — important infrastructure organizations in Vietnam need to be placed in the threat model.
Visibility Issue
Most organizations in Vietnam — including enterprises — have zero visibility at the SOHO/IoT layer. Remote workers' routers, office security cameras, factory IoT devices: these devices are often not within the scope of security monitoring. JDY shows that this is exactly where the attacker is building foothold.yen Gia
Recommended
Immediate (0–24 hours)
Inventory SOHO/IoT devices now
Scan internal network to detect running SOHO/IoT devices
Prioritize vendors: Ubiquiti, Draytek, Hikvision, Linksys, Araknis, Mimosa, Cisco RV series
- nmap -sV -p 80,443,8080,8443,23,22,8888 <internal_subnet>
--script http-title,banner
-oX soho_iot_inventory.xml
- nmap -sV -p 80,443,8080,8443,23,22,8888 <internal_subnet>
Verify which devices are exposing to the internet
Check external exposure
- nmap -sV <public_ip_range> -p 80,443,8080,8443,22,23,8888
Or use Shodan/Censys with org filter
Patch CVE-2026-35616 immediately on Fortinet
Short-term (1–7 days)
Implement network segmentation cho IoT
Private VLAN for SOHO/IoT devices
Firewall rules: IoT VLAN is only allowed to go to the internet, not access corporate network
Block outbound Tor from corporate and IoT networks
Block TCP port 9050, 9150, 443 to known Tor exit nodes
Enable logging and monitoring for edge devices
Detection rule for SIEM (Splunk/Elastic format):
index=network sourcetype=firewall (dest_port=9050 OR dest_port=9150)
| stats count by src_ip, dest_ip, dest_port
| where count > 10
| comment "Outbound Tor từ internal device — nghi vấn C2"
Detect abnormal SYN scan behavior from internal device:
index=network sourcetype=firewall action=allow
| stats dc(dest_ip) as unique_dests by src_ip, _time span=1h
| where unique_dests > 500
| comment "High-rate scanning từ internal host — nghi vấn botnet"
Password reset and firmware update throughout SOHO/IoT
Change default credentials
Disable remote management if not needed
Update firmware to the latest version
Disable UPnP
Long-term
Deploy continuous asset discovery:
Integrate IoT/OT devices into asset inventory platform (Axonius, Armis, or equivalent)
Scheduled periodic scanning to detect new unauthorized devices
Threat Intelligence Feed about China-nexus TTPs:
Subscribe Lumen Black Lotus Labs feed
Follow CISA Advisories on Volt Typhoon, Salt Typhoon
Integrate IOC feed into SIEM/firewall automatically
Re-evaluate Remote Work Security Policy:
Remote workers' SOHO devices risk expanding the attack surface of the corporate network
Consider Zero Trust Access instead of traditional VPN to reduce the risk of compromise from uncontrolled devices
Reference
China-Linked JDY Botnet Expands to 1,500+ Devices for Cyber Reconnaissance
Expanded JDY IoT and SOHO botnet enables rapid vulnerability exploitation
JDY Botnet Evolves After KV Takedown, Targets Military Networks
China-linked JDY botnet expands targeting of U.S. military networks
