agency-testts (npm) · Malicious Code
Affects agency-testtsSource GCVE Database
Malicious package : remove agency-testts and rotate any secrets on hosts that installed it.
Data as of 25 Sep 2026, 04:49 UTC
Malicious package
Published to npm · OSV MAL-2026-17171
What to do
Remove agency-testts from every project, lockfile and image that pulls it in. Treat any host that installed it as compromised: rotate the credentials, tokens and keys it could read, from a clean machine.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| npmagency-testts | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
Description
--- _-= Per source details. Do not edit below this line.=-_ ## Source: amazon-inspector (ac3bbe97b41f8d8d1a74e9f369318620c08d648365a4e78d49d1da31d085531d) package.json declares a postinstall lifecycle hook `wscript.exe 4444.vbs` that auto-runs on `npm install` on Windows. The bundled 4444.vbs is a ~674KB script containing large opaque base64 blobs and an AES key/IV pair (`stateFKK`, `manifestGCP`) which it uses at runtime to decrypt an embedded payload via `CreateDecryptor().TransformFinalBlock` and hand it to `C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe` for execution. After staging, the script self-cleans with `cmd.exe /c ping 127.0.0.1 -n 8 >nul & del /f /q... & rmdir /s /q...` to remove its own artifacts. Cover-story comments label the script a `Sync Agent — diagnostic telemetry collector` from a fictitious `Wingtip Toys Corporation`, but the code performs no telemetry-shaped behavior — it decrypts and executes an opaque payload. The package ships no other functionality; installing it on Windows results in arbitrary attacker code running under the installer's user account.