MAL-2026-17317

    Dashboard / Malicious Package / MAL-2026-17317

    MAL-2026-17317

    Published: 30 Sept 2026Last Modified: 30 Sept 2026

    Summary: Malicious code in booking-tasks (npm)

    Details: Source: amazon-inspector (08305a6c73bd94f2983c949316cb78fef7f7169f85523a773c94fb305874e063) The package's package.json declares a postinstall hook `wscript.exe 4444.vbs` that fires automatically on `npm install`. The bundled 4444.vbs contains hand-rolled AES-128 (with XOR-masked forward/inverse S-boxes), a ChaCha20-IETF stream, XOR-masked SHA-256 round constants, a Base64 decoder via MSXML DOM, and a chunked Base64 ciphertext blob (ArtifactBundleHX, ~665 chunks). At install time the VBScript decrypts these chunks into a PowerShell loader, writes it to %TEMP%\pf<rand>.dat, and hands it to powershell.exe for process hollowing, giving the publisher arbitrary code execution on the installer's Windows host. The shipped library surface (src/index.js) is a small Zod-validated `checkEligibility()` function that never references 4444.vbs, and readme.md states 'No network requests. No personal data storage. No installation scripts.' — a direct contradiction of the declared postinstall hook, indicating the source module is a decoy for the dropper. The multi-primitive crypto and chunked-Base64 encoding of the payload serve only to hide executable content from static inspection.

    Affected packages

    Package

    Name: booking-tasks

    Purl: pkg:npm/booking-tasks

    Affected ranges

    Type: N/A

    Events:

    Introduced- None
    Fixed -None

    Affected versions

    1.0.2