MAL-2026-6487 Malicious code in velocityfix (npm)

Package masquerades as 'Performance fixes for Minecraft Velocity proxy' authored by 'Velocity Team' — Velocity is a Java project from PaperMC and has no legitimate npm distribution. package.json declares scripts.postinstall = 'node scripts/loader.js', which silently spawns a bundled payload.exe via start /b on every npm install. The bundled PE contains a hardcoded C2 at https://751.lol/upload/ and posts a multipart form with fields username, os_info, ip_address, and file=data.zip — exfiltrating the installer's hostname, OS, IP, and a zip of collected files to an attacker-controlled host. The payload labels itself [INJECTOR], reads registry values (ProductName, DisplayVersion), and performs sandbox / VM evasion (probes for SbieDll.dll, snxhk.dll, Vboxguest.sys, vmGuestLib.dll, VMware/VirtualBox artifacts) so it only fully detonates on real victim hosts. The combination of brand-impersonation lure, install-time auto-execution of an opaque native binary, hardcoded exfil endpoint, and anti-analysis evasion is an unambiguous Windows-targeted supply-chain dropper.

Any computer that has this package installed or running should be considered fully compromised. All secrets and keys stored on that computer should be rotated immediately from a different computer. The package should be removed, but as full control of the computer may have been given to an outside entity, there is no guarantee that removing the package will remove all malicious software resulting from installing it.