OpenSSF/OSV advisory MAL-2026-14154 confirms this npm version as malicious. Package name is a one-character typosquat of the widely-used 'typescript' family. On npm install, scripts/postinstall.js XOR-decodes (key 'stf2026') a GitHub-hosted URL held as an integer array and downloads a Windows PE to TEMP\main.exe, then spawns it detached with no hash or signature verification...
Source
OpenSSF Malicious Packages via OSV
Summary
Malicious code in typesript-cli (npm)
Details
Package name is a one-character typosquat of the widely-used 'typescript' family. On npm install, scripts/postinstall.js XOR-decodes (key 'stf2026') a GitHub-hosted URL held as an integer array and downloads a Windows PE to TEMP\main.exe, then spawns it detached with no hash or signature verification. When running under WSL or virtualized Linux (detected via /proc/version and WSLENV), the script decodes a bridge launcher command and inline script from further XOR-obfuscated blobs and executes them via child_process.exec with windowsHide:true to fetch and run the same payload on the Windows host, crossing the Linux sandbox boundary. The script also POSTs platform info to a hardcoded bare-IP endpoint http://193.70.34.101:20099/vote, with the IP split across a string array ['193','70','34','101'].join('.') to hide it from static review, serving as an install beacon.
Decision reason
OpenSSF Malicious Packages via OSV confirms typesript-cli@1.0.0 as malicious (MAL-2026-14154): Malicious code in typesript-cli (npm)