Malicious code in booking-tasks (npm)

CISA KEV is observed exploitation evidence. FIRST EPSS is a dated prediction of exploitation in the next 30 days. Missing scores are unknown. This collector requests predictions only for explicit CVE aliases in the public NuGet archive; Microsoft release views retain their existing prediction scope.

No collected risk observation for these identifiers. This does not establish absence of exploitation or a zero probability.

--- _-= Per source details. Do not edit below this line.=-_ ## 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.

Source published

30 Sep 2026 03:05:04 UTC

Source modified

30 Sep 2026 03:30:04 UTC

Observed here

24 Oct 2026 13:17:17 UTC

Source terms

OSV · upstream source license applies

Original source record · Cite this exact observation · Complete original publisher JSON

This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: osv · OSV · upstream source license applies. Source text is retained; field grouping and change labels are provided by ChangeIntel.