Which versions of simple-node-calc-b are malicious?

The following npm versions of simple-node-calc-b are flagged malicious: 1.0.0. Treat any of these as compromised.

How do I remediate simple-node-calc-b if I installed it?

Remove simple-node-calc-b 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.

I already installed simple-node-calc-b — how do I know if it already compromised me?

If simple-node-calc-b 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.

Is simple-node-calc-b part of a known attack campaign?

Yes — simple-node-calc-b is associated with the IN-MAL-2026-007504 campaign. Packages in the same campaign often share infrastructure and payloads, so check whether any related packages are also in your dependency tree.

How do I find simple-node-calc-b across my projects, lockfiles, and CI pipelines?

Scan your lockfiles (package-lock.json, pnpm-lock.yaml, yarn.lock, requirements.txt, poetry.lock, etc.) and build artifacts for simple-node-calc-b (version 1.0.0). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging simple-node-calc-b across your stack and pipelines.

Malicious package

simple-node-calc-bnpm

Malicious code in simple-node-calc-b (npm) Remove it immediately and rotate any exposed credentials.

MAL-2026-6453

Immediate action

Remove the package, then rotate any secrets the build/runtime could reach.

npm uninstall simple-node-calc-b

What this malware does

[email protected] ships a binding.gyp that includes a modules file declaring "lodash": "<!(node lodash-compiler.js)". The gyp <!(...) syntax executes shell commands at parse time, and npm auto-invokes node-gyp on any package containing binding.gyp during npm install, so node lodash-compiler.js runs automatically on every install with no user opt-in. lodash-compiler.js is an 87KB obfuscator.io-style packed script (524-entry rotated string array _0x2f6e, decoder wrapper, control-flow flattening switch/case dispatcher, hex variable names) reachable through this auto-execution path. The script body contains require('fs').writeFileSync(...) along with string-array fragments 'poc.txt', 'Security P', 'OC.', 'writeFileS', 'ync' — self-describing as a proof-of-concept payload. The package name advertises a calculator; there is no legitimate reason for a calculator to ship 87KB of obfuscated code behind a hidden gyp shell-expansion. The combination of auto-execution on default install, heavy obfuscation, purpose mismatch, and self-described POC payload matches the canonical install-time RCE pattern.

Malicious versions

1 flagged

1.0.0

Indicators of compromise (SHA-256)

78b115418f82ef73f995f3bf6b0cb8bf50da516b56c691b76ccb939491d2b046

Detection & response playbook

Malicious package

Find it
Scan your lockfiles (package-lock.json, pnpm-lock.yaml, yarn.lock, requirements.txt, poetry.lock, etc.) and build artifacts for simple-node-calc-b (version 1.0.0). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging simple-node-calc-b across your stack and pipelines.
If you installed it — respond
Remove simple-node-calc-b 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 simple-node-calc-b 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 simple-node-calc-b 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

No. simple-node-calc-b on npm has been identified as a malicious package (version 1.0.0 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

IN-MAL-2026-007504

References

npmjs.com

Credits

Amazon Inspector · finder

Detect & block this

O3 blocks simple-node-calc-b-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.

Malware detection Runtime egress monitoring