MAL-2026-17553 Malicious code in css-ikomdq-polyfill (npm)

Malicious package Published
Package
css-ikomdq-polyfill
Registry
npm

What is MAL-2026-17553?

MAL-2026-17553 is a malicious package in css-ikomdq-polyfill, published on 5 Oct 2026.

Official description

The package presents itself as a CSS polyfill but ships thunderboltRegistry.js, which on require() executes a top-level IIFE that runs id, whoami, uname -a, ifconfig/ip addr, and reads /etc/hosts via child_process.execSync, then posts the command outputs together with hostname, node version, platform, and pid to the hardcoded plain-HTTP endpoint http://dxpoc.gt.tc/callback.php/ using fetch. The module also deletes its own entries from require.cache so the payload re-runs on each require() rather than being memoized. The package name and the thunderbolt/editor/corvid Proxy facade impersonate Wix parastorage registry modules to encourage accidental installation.

What should I do about MAL-2026-17553?

Remove the package from your dependencies and lockfiles, then rotate any secrets on machines where it was installed.

Sources

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