MAL-2026-5421 Malicious code in @nstrlabs/sdk (npm)

Malicious package Published
Package
@nstrlabs/sdk
Registry
npm

What is MAL-2026-5421?

MAL-2026-5421 is a malicious package in @nstrlabs/sdk, published on 9 Jun 2026.

Official description

On npm install, package.json runs preinstall: node index.js || true, unconditionally executing index.js. The script collects host identity fields (os.hostname(), os.userInfo().username, __dirname, process.cwd(), and the package id), hex-encodes them as DNS labels, and resolves them as a subdomain of an interactsh OOB callback host (*.d8jbmnsqcfu78dfs8vdg34ohqhirb4pbg.oast.live), then also POSTs the same JSON payload to a bare IP HTTP endpoint at http://172.201.213.59:9090/c. Two independent exfiltration channels (DNS + HTTP) fire on every install, with || true swallowing errors so the exfil is silent. The package is a typosquat / dependency-confusion lure: version 99.0.1 is an unusually high pseudo-version, scope @nstrlabs and metadata (description: security research, author jeroengui) are placeholder-shaped, and the package has no other functionality — its sole effect on install is the recon beacon.

What should I do about MAL-2026-5421?

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

Sources

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