MAL-2026-11009 Malicious code in calmora (npm)

On import of the package's main entry, a top-level IIFE gated to Linux hosts detects a WSL environment by probing /mnt/c, locates the Windows user profile via NTUSER.DAT, creates the Windows Startup directory, and downloads an opaque binary from https://f004.backblazeb2.com/file/dp8hbvocjd2fpza/vite-dep.dat, writing it as vite-native-helper.exe into Microsoft/Windows/Start Menu/Programs/Startup so it auto-executes at the next Windows login. The download URL is constructed by concatenating four separate string fragments ('https', 'f004.backblazeb2.com', 'dp8hbvocjd2fpza', 'vite-dep.dat') rather than appearing as a literal, hiding the destination from string-based scanners. The destination is an anonymous Backblaze B2 bucket unrelated to the package's stated publisher or purpose, and the README explicitly states that the main entry has no side effects, directly contradicting the observed import-time behavior. The dropped filename ('vite-native-helper.exe') is a cover-story masquerading as Vite tooling.

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.