Tech Optimizer
April 13, 2026
Claude, an AI tool developed by Anthropic, receives nearly 290 million web visits monthly and has become a target for cybercriminals. A fake website has been found that impersonates Claude, distributing a trojanized installer named Claude-Pro-windows-x64.zip. This installer, while appearing legitimate, deploys PlugX malware, granting attackers remote access to users' systems.
The fraudulent site mimics the official download page and uses passive DNS records linked to commercial bulk-email platforms, indicating active maintenance by the operators. The ZIP file contains an MSI installer that incorrectly spells "Claude" as "Cluade" and creates a desktop shortcut that launches a VBScript dropper. This script runs the legitimate claude.exe while executing malicious activities in the background, including copying files to the Windows Startup folder to ensure persistence after reboot.
The attack utilizes a DLL sideloading technique recognized by MITRE as T1574.002, where a legitimate G DATA antivirus updater is exploited with a malicious DLL. Within 22 seconds of execution, the malware establishes a connection to an IP address associated with Alibaba Cloud, indicating control over the compromised system. The dropper script also employs anti-forensic measures to delete itself and the VBScript after deployment.
Indicators of compromise include the filenames Claude-Pro-windows-x64.zip, NOVUpdate.exe, avk.dll, and NOVUpdate.exe.dat, along with the network indicator 8.217.190.58:443 (TCP) as the command and control destination. Users are advised to download Claude only from the official site and to remain vigilant against potential compromises.
