Which versions of cjs-biginteger are malicious?

The following npm versions of cjs-biginteger are flagged malicious: 5.0.3, 5.0.5, 5.0.6. Treat any of these as compromised.

How do I remediate cjs-biginteger if I installed it?

cjs-biginteger 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.

I already installed cjs-biginteger — how do I know if it already compromised me?

If cjs-biginteger 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 cjs-biginteger part of a known attack campaign?

Yes — cjs-biginteger is associated with the GHSA-65gr-98mv-9rj5 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 cjs-biginteger 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 cjs-biginteger (3 malicious versions). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging cjs-biginteger across your stack and pipelines.

Malicious package

cjs-bigintegernpm

cjs-biginteger is a confirmed malicious npm package (MAL-2026-2882) that steals credentials and exfiltrates sensitive data (malicious versions 5.0.3, 5.0.5, 5.0.6). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in cjs-biginteger (npm)

MAL-2026-2882

Immediate action

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

npm uninstall cjs-biginteger

What this malware does

big.js typosquat campaign - SSH backdoor implantation, credential and crypto wallet theft

The package cjs-biginteger was found to contain malicious code.

Any computer that has this package installed or running should be considered fully compromised. All secrets and keys stored on that computer should be rotated immediately from a different computer. The package should be removed, but as full control of the computer may have been given to an outside entity, there is no guarantee that removing the package will remove all malicious software resulting from installing it.

Malicious versions

3 flagged

5.0.35.0.55.0.6

Indicators of compromise (SHA-256)

ad18a38aa59b5edbd05dbdf229f4d013446f970fe18b41e54ffc1c24a926d2bd

cff43da02f0b711c032c5ef6661cd0334669e4ddd1b0d82b0b06ae8e989d3847

Detection & response playbook

Credential / info stealer

Find it
Scan your lockfiles (package-lock.json, pnpm-lock.yaml, yarn.lock, requirements.txt, poetry.lock, etc.) and build artifacts for cjs-biginteger (3 malicious versions). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging cjs-biginteger across your stack and pipelines.
If you installed it — respond
cjs-biginteger 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 cjs-biginteger 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 cjs-biginteger 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. cjs-biginteger on npm has been identified as a malicious package (versions 5.0.3, 5.0.5, 5.0.6 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

GHSA-65gr-98mv-9rj5

References

Credits

Amazon Inspector · finder
SafeDep · finder

Detect & block this

O3 blocks cjs-biginteger-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the credential exfiltration and severs the channel.

Malware detection Runtime egress monitoring

Explore

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