calculator-preinstall-hook-demo (npm) · Malicious Code
Affects calculator-preinstall-hook-demoSource GCVE Database
Malicious package : remove calculator-preinstall-hook-demo and rotate any secrets on hosts that installed it.
Data as of 2 Nov 2026, 08:45 UTC
Malicious package
Published to npm · OSV MAL-2026-18454
What to do
Remove calculator-preinstall-hook-demo from every project, lockfile and image that pulls it in. Treat any host that installed it as compromised: rotate the credentials, tokens and keys it could read, from a clean machine.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| npmcalculator-preinstall-hook-demo | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
Description
The npm package calculator-preinstall-hook-demo version 1.1.2 contains malicious code that executes a preinstall script during installation. This script sends the machine's hostname and OS username to a Discord webhook, potentially leaking sensitive environment information. The package was published by the npm account bigdevin55 and is pulled in as a dependency by calculator-preinstall-chain-demo@1.1.2.