Which versions of bn-lint are malicious?

The following npm versions of bn-lint are flagged malicious: 3.0.8. Treat any of these as compromised.

How do I remediate bn-lint if I installed it?

bn-lint is a typosquat — you almost certainly intended a legitimately-named package. Remove bn-lint, install the correct package, and rotate any secrets exposed during the install since post-install scripts may have already run.

I already installed bn-lint — how do I know if it already compromised me?

If bn-lint 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 bn-lint part of a known attack campaign?

Yes — bn-lint is associated with the IN-MAL-2026-007428 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 bn-lint 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 bn-lint (version 3.0.8). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging bn-lint across your stack and pipelines.

Malicious package

bn-lintnpm

Malicious code in bn-lint (npm) Remove it immediately and rotate any exposed credentials.

MAL-2026-6376

Immediate action

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

npm uninstall bn-lint

What this malware does

Package is published as 'bn-lint' but ships a verbatim copy of MikeMcl/big.js (README, source, version banner v7.0.1, and repo URL all identify as big.js). Both entrypoints, big.js and big.mjs, have been modified at lines 605-606 to inject const helper = require("ts-bn-lint-helper"); helper.from_str().then(e => e).catch(e => { }); at module top level. Any require('bn-lint') or import of the package immediately loads and invokes the separately-published, pinned [email protected] (declared in package.json line 58). The .then(e => e).catch(e => { }) wrapping silently swallows both resolution and rejection values, suppressing logs, thrown errors, and rejected promises so the secondary payload's execution is invisible to a developer using what they believe to be a big.js arithmetic library. The combination of impersonated identity, top-level loader injection into an otherwise unrelated arithmetic library, a pinned untrusted second-stage dependency, and deliberate error suppression is consistent with a typosquat-with-payload supply-chain attack rather than a legitimate fork.

Malicious versions

1 flagged

3.0.8

Indicators of compromise (SHA-256)

c14057d91b2283926b2b0c1093a66db17c40efbd0ceb21c29b0bdbfa79736da5

Detection & response playbook

Typosquat

Find it
Scan your lockfiles (package-lock.json, pnpm-lock.yaml, yarn.lock, requirements.txt, poetry.lock, etc.) and build artifacts for bn-lint (version 3.0.8). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging bn-lint across your stack and pipelines.
If you installed it — respond
bn-lint is a typosquat — you almost certainly intended a legitimately-named package. Remove bn-lint, install the correct package, and rotate any secrets exposed during the install since post-install scripts may have already run.
Did it already run?
If bn-lint 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 bn-lint 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. bn-lint on npm has been identified as a malicious package (version 3.0.8 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

IN-MAL-2026-007428

References

npmjs.com

Credits

Amazon Inspector · finder

Detect & block this

O3 blocks bn-lint-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