HVNC Backdoor Targets LATAM Organizations with Fake Tax and DocuSign Lures
A custom HVNC backdoor is targeting Latin American financial organizations via fake DocuSign and NFe tax-document lures, giving attackers hidden persistent remote access.
ANY.RUN researchers analyzed a multi-stage phishing campaign delivering a custom HVNC backdoor to banking and financial organizations in Latin America. The chain starts with fake DocuSign and NFe tax-document pages that serve per-visitor ZIP archives, followed by an LNK dropper, an NSIS loader, and a 64-bit backdoor masquerading as Windows Update Assistant. The implant provides hidden remote desktop control, keystroke monitoring, Firefox data theft, Startup-folder persistence, and EDR-aware behavior, communicating over TCP/27015.
Muhstik Botnet Attacks Tomato Routers to Harvest New IoT Devices
Unit 42 found a Muhstik botnet variant brute-forcing Tomato router web authentication to harvest IoT devices for crypto mining and DDoS attacks.
Palo Alto Networks Unit 42 researchers in December 2019 identified a new Muhstik botnet variant scanning Tomato routers on TCP 8080 and brute-forcing default admin credentials, targeting roughly 4,600 exposed devices found via Shodan. The variant also scans WordPress and Webuzo installations and exploits the Oracle WebLogic deserialization flaw CVE-2019-2725 for unauthenticated remote code execution. Muhstik, active since March 2018, self-propagates like a worm and typically monetizes infections through cryptocurrency mining and DDoS attacks controlled via an IRC C2 channel.
Home & Small Office Wireless Routers Exploited to Attack Gaming Servers
Unit 42 details an updated Gafgyt botnet variant exploiting Zyxel, Huawei, and Realtek router vulnerabilities to recruit devices for DoS attacks on gaming servers.
Unit 42 researchers identified an updated Gafgyt variant derived from the JenX botnet that combines three remote code execution exploits: CVE-2017-18368 (Zyxel P660HN-T1A), CVE-2017-17215 (Huawei HG532), and CVE-2014-8361 (Realtek RTL81XX chipset). Shodan scans show more than 32,000 wireless routers worldwide potentially vulnerable to these exploits. The exploits act as droppers, pulling architecture-specific binaries from a malicious server (185.172.110.224), and the botnet performs denial-of-service attacks against gaming servers, most notably Valve Source engine servers.