OpenSSF/OSV advisory MAL-2026-14145 confirms this npm version as malicious. typecript-cli@1.0.0 is a typosquat of 'typescript' whose scripts/postinstall.js performs an install-time dropper attack. Payload strings are stored as integer arrays and XOR-decoded at runtime with key 'stf2026' via an unpackSegment() helper, hiding the download URL and PowerShell command from static scanners. On Windows hosts, the script downloads main.exe from...
Source
OpenSSF Malicious Packages via OSV
Summary
Malicious code in typecript-cli (npm)
Details
typecript-cli@1.0.0 is a typosquat of 'typescript' whose scripts/postinstall.js performs an install-time dropper attack. Payload strings are stored as integer arrays and XOR-decoded at runtime with key 'stf2026' via an unpackSegment() helper, hiding the download URL and PowerShell command from static scanners. On Windows hosts, the script downloads main.exe from https://github.com/bebraz1/<repo>/releases/download/<tag>/main.exe (a personal GitHub account unrelated to the package publisher) to %TEMP%/main.exe, then spawns it detached with no hash or signature verification. When running under WSL, the script uses an exec() bridge that invokes powershell.exe on the Windows host to escape the Linux install sandbox and execute the same payload. Postinstall also POSTs a JSON body with the resolved platform label to a hardcoded bare-IP endpoint at http://193.70.34.101:20099/vote, with the IP assembled from a split octet array (['193','70','34','101'].join('.')) to evade string matching, serving as an install beacon and host selector.
Decision reason
OpenSSF Malicious Packages via OSV confirms typecript-cli@1.0.0 as malicious (MAL-2026-14145): Malicious code in typecript-cli (npm)