@nstrlabs/utilsnpm
Advisory published Updated
@nstrlabs/utils is a confirmed malicious npm package (MAL-2026-5423) that steals credentials and exfiltrates sensitive data (malicious versions 99.0.0, 99.0.1). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in @nstrlabs/utils (npm)
What this malware does
On npm install, the package's preinstall script (node index.js || true) executes automatically and collects host identifiers from the installer's machine — os.hostname(), os.userInfo().username, __dirname, and process.cwd() — then exfiltrates them through two channels. First, the JSON payload is POSTed to a hardcoded bare IP http://172.201.213.59:9090/c. Second, the data is hex-encoded into a subdomain and resolved via DNS against *.d8jbmnsqcfu78dfs8vdg34ohqhirb4pbg.oast.live, an Interactsh out-of-band beacon. The || true suffix swallows any error so the install always succeeds silently. Although the package metadata describes itself as 'security research', every installer is harmed: host reconnaissance fires unconditionally on install with no opt-out and no disclosure.
Malicious versions
Indicators of compromise (SHA-256)
Detection & response playbook
Credential / info stealerFind it
Search your lockfiles and build artifacts for @nstrlabs/utils (2 malicious versions).
If you installed it — respond
@nstrlabs/utils is built to steal secrets, so assume every credential the build or runtime could read is compromised. Remove it from your project and lockfile, then rotate ALL exposed secrets — npm/registry tokens, cloud keys, CI/CD secrets, SSH keys, and any .env values — from a known-clean machine. Audit logs for unauthorized use of those credentials.
Did it already run?
If @nstrlabs/utils was installed, its post-install payload may already have run. Removing the package does not undo that — check outbound connections and credential use from the install window onward.
Frequently asked questions
Campaign
References
Credits
- Amazon Inspector · finder
Detect & block this
O3 blocks @nstrlabs/utils-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the credential exfiltration and severs the channel.