typescriptt-corenpm
typescriptt-core is a confirmed malicious npm package (MAL-2026-14152) that opens a backdoor for remote access (malicious version 1.0.0). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in typescriptt-core (npm)
What this malware does
typescriptt-core is a typosquat of the TypeScript ecosystem (double-t) with an empty main (module.exports = {}) and no library functionality. The only code that runs is scripts/postinstall.js, which XOR-decodes a hidden URL and PowerShell launcher using the fixed key 'stf2026' and, on Windows, downloads main.exe from https://github.com/bebraz1/qPzM50V1AKG0rVlH/releases/download/null/main.exe to %TEMP% and spawns it detached. On WSL, the same script decodes a bridge command and invokes powershell.exe on the Windows host to perform the same fetch-and-run. Before the drop, postinstall POSTs a small JSON payload containing the host platform label to a hardcoded bare-IP endpoint http://193.70.34.101:20099/vote over plain HTTP as an install beacon. The destination GitHub account (bebraz1) is unrelated to the TypeScript project, the payload is opaque, and both the URL and the PowerShell command are XOR-obfuscated to defeat static review.
Malicious versions
Indicators of compromise (SHA-256)
Detection & response playbook
Backdoor / remote accessFind it
Search your lockfiles and build artifacts for typescriptt-core (version 1.0.0).
If you installed it — respond
typescriptt-core establishes remote access, so treat any host that installed it as fully compromised. Isolate the machine, remove the package, rotate all credentials it could reach, and rebuild from a trusted image rather than cleaning in place — a backdoor may have planted additional persistence.
Did it already run?
If typescriptt-core was installed, its post-install payload may already have run. Removing the package does not undo that — check outbound connections and credential use from the install window onward.
Frequently asked questions
Campaign
References
Credits
- Amazon Inspector · finder
Detect & block this
O3 blocks typescriptt-core-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the C2 callback and severs the channel.