Chinese-linked actors exploit VMware ESXi via SonicWall VPN
🔍 Huntress says Chinese-speaking threat actors used a compromised SonicWall VPN appliance in December 2025 to deploy a multi-stage exploit against VMware ESXi, leveraging three zero-day vulnerabilities disclosed by Broadcom in March 2025 (CVE-2025-22224/22225/22226). The toolkit includes an orchestrator dubbed MAESTRO, an unsigned kernel driver loaded via KDU, and a VSOCK-based ELF backdoor called VSOCKpuppet. The attack chain enabled VM-to-hypervisor escapes, remote control of ESXi hosts over VSOCK port 10000, and file transfer capabilities from guest VMs, all of which were halted by Huntress before a suspected ransomware stage could complete.
