multi-acctnpm
multi-acct is a confirmed malicious npm package (MAL-2026-13371) that executes malicious code on install (malicious versions 1.0.0, 2.0.999, 2.1.999…). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in multi-acct (npm)
What this malware does
[email protected] is a near-empty wrapper (index.js is a two-line stub returning name/version literals; author is the generic 'Package Registry' and repository.url points at an example.com-style placeholder). Its sole functional dependency, vector-cursor-stream-engine, is not resolved from the npm registry but from a hardcoded third-party HTTPS URL, https://artifacts.yosiroute.com/npm/vector-cursor-stream-engine, and the shrinkwrap marks that dependency as hasInstallScript:true. On npm install, npm downloads the tarball from artifacts.yosiroute.com and executes its lifecycle scripts, so whoever controls that host gets arbitrary code execution on the installer's machine. The URL is unpinned and carries no integrity hash, so the delivered bytes can change at any time. The wrapper shape (placeholder metadata, trivial main, single off-registry dependency with install scripts) matches a dependency-confusion / lure package whose real payload is delivered through the fetched sub-tarball.
Malicious versions
Indicators of compromise (SHA-256)
Detection & response playbook
Malicious packageFind it
Scan your lockfiles (package-lock.json, pnpm-lock.yaml, yarn.lock, requirements.txt, poetry.lock, etc.) and build artifacts for multi-acct (10 malicious versions). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging multi-acct across your stack and pipelines.
If you installed it — respond
Remove multi-acct from your project and lockfile, then assume any secrets accessible to the build or runtime were exposed: rotate API keys, tokens, and credentials, and audit for unexpected outbound activity or persistence.
Did it already run?
If multi-acct was ever installed, its post-install/runtime payload may have already executed. O3's L7 egress monitoring and runtime eBPF sensors detect the credential exfiltration or command-and-control callback after install and block the malicious outbound channel, so you catch and contain the actual compromise — not just the presence of the package.
How O3 protects you
O3 blocks multi-acct before install through its supply-chain scanner, and if it has already run, detects and severs the exfiltration or C2 callback at runtime through L7 egress monitoring and eBPF.
Frequently asked questions
Campaign
References
Credits
- Amazon Inspector · finder
Detect & block this
O3 blocks multi-acct-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the malicious outbound activity and severs the channel.