OpenSSF/OSV advisory MAL-2026-11546 confirms this npm version as malicious. Package advertises a trivial formatDate utility but ships a malicious npm postinstall hook. The postinstall script launches a backgrounded interactive bash reverse shell via /dev/tcp/124.221.154.135/4444, granting a remote party shell access on the installer's host at install time. A companion postinstall.js reads the installer's ~/.ssh directory listing along with OS username/platform information and POSTs it over...
Source
OpenSSF Malicious Packages via OSV
Summary
Malicious code in simple-date-formatter-util-6 (npm)
Details
Package advertises a trivial formatDate utility but ships a malicious npm postinstall hook. The postinstall script launches a backgrounded interactive bash reverse shell via /dev/tcp/124.221.154.135/4444, granting a remote party shell access on the installer's host at install time. A companion postinstall.js reads the installer's ~/.ssh directory listing along with OS username/platform information and POSTs it over HTTPS to the same hardcoded IP (124.221.154.135:443, path /post). The advertised formatDate export in index.js is a decoy; the package name pattern and empty author metadata are consistent with a typosquat/decoy lure whose sole functional effect is install-time compromise of the installer machine.
Decision reason
OpenSSF Malicious Packages via OSV confirms simple-date-formatter-util-6@1.0.0 as malicious (MAL-2026-11546): Malicious code in simple-date-formatter-util-6 (npm)