MAL-2026-18454: Malicious code in calculator-preinstall-hook-demo (npm)

calculator-preinstall-hook-demo@1.1.2 presents itself as a test fixture for npm lifecycle hooks. Its preinstall script runs node preinstall.js on npm install, which POSTs the machine's hostname and the OS username to the Discord webhook https://discord.com/api/webhooks/1566215853794394162/xsqpEbSn-cc3DU2AKWdzqWnXX5hjTfV-gUePQZ4evrHGlZctMd40TKCrN42qnJd7moc1. It was published by the npm account bigdevin55 together with calculator-preinstall-chain-demo@1.1.2, which pulls it in as a dependency.

--- -= Per source details. Do not edit below this line.=-

Source: ghsa-malware (db06ea25b6b764475357882b39d46919c5c083785f24d7ab2a264085acb01d81) Any computer that has this package installed or running should be considered fully compromised. All secrets and keys stored on that computer should be rotated immediately from a different computer. The package should be removed, but as full control of the computer may have been given to an outside entity, there is no guarantee that removing the package will remove all malicious software resulting from installing it.