MAL-2026-18187 Malicious code in simplewave (npm)

Malicious package Published
Package
simplewave
Registry
npm

What is MAL-2026-18187?

MAL-2026-18187 is a malicious package in simplewave, published on 22 Oct 2026.

Official description

[email protected] declares a postinstall script in package.json that runs an inline Node command performing an HTTP GET to a subdomain of oast.fun with the installer's os.hostname() embedded as the leftmost DNS label. oast.fun is the public Interactsh out-of-band interaction server, used to receive exfiltrated data via DNS/HTTP callbacks. The beacon fires unconditionally on npm install, with no caller consent or configuration. The shipped index.js is a trivial stub providing no advertised functionality, so the manifest-level beacon is the package's entire effect. The host identifier of every machine that installs the package is delivered to a third-party OOB collector controlled by whoever provisioned the oast.fun subdomain token.

What should I do about MAL-2026-18187?

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

Sources

Is MAL-2026-18187 in your software?

Upload an SBOM and sbomify checks it against every vulnerability here, every day.

Check your SBOMs for free