Hijacked ScreenConnect Clients Spread Worm-Like Malware to Remote Support Systems

Huntress identified a campaign in which attackers use social engineering—including fake technical support, phishing, fraudulent refund-search results, and Quick Assist abuse—to persuade victims to install trojanized ConnectWise ScreenConnect clients. Rather than exploiting a ScreenConnect vulnerability, the altered remote-support software detects incoming sessions and uses ScreenConnect file-transfer and remote-execution functions to send a staged four-part VBScript loader to the connecting endpoint, potentially infecting technician and help-desk systems without further user interaction.

The payload chain profiles hosts, establishes persistence, seeks elevated execution, and can deploy remote-access, tunneling, and cryptocurrency-mining tools while attempting to evade security controls, including Microsoft Defender reporting and User Account Control. Huntress observed the activity at unrelated organizations during late-August incidents and advises organizations to reimage confirmed compromised systems, review ScreenConnect deployments and audit logs, and investigate suspicious Windows Script Host or PowerShell execution linked to ScreenConnect sessions.