Which versions of bjs-biginteger are malicious?

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

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

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

If bjs-biginteger 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.

Is bjs-biginteger part of a known attack campaign?

Yes — bjs-biginteger is associated with the GHSA-jjf3-wfhw-qhx4 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 bjs-biginteger across my projects, lockfiles, and CI pipelines?

Search your lockfiles and build artifacts for bjs-biginteger (2 malicious versions).

Malicious package

bjs-bigintegernpm

Advisory published Apr 14, 2026Updated Jul 6, 2026

bjs-biginteger is a confirmed malicious npm package (MAL-2026-2879) that steals credentials and exfiltrates sensitive data (malicious versions 5.0.5, 5.0.6). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in bjs-biginteger (npm)

MAL-2026-2879

Immediate action

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

npm uninstall bjs-biginteger

What this malware does

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

The package bjs-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

2 flagged

5.0.55.0.6

Indicators of compromise (SHA-256)

ce3bc89babfc42de2e7df569ebf26d41dcc13469a19895aa4144c2625ddbd87b

fa9a45f5b0c330db1b8359e0dc4dfe9151c922ee47424de29c565cbd5e2fc3d0

Detection & response playbook

Credential / info stealer

Find it
Search your lockfiles and build artifacts for bjs-biginteger (2 malicious versions).
If you installed it — respond
bjs-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 bjs-biginteger 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

No. bjs-biginteger on npm has been identified as a malicious package (versions 5.0.5, 5.0.6 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

GHSA-jjf3-wfhw-qhx4

References

Credits

Amazon Inspector · finder
SafeDep · finder

Detect & block this

O3 blocks bjs-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

All malware advisories How O3 detects malware Vulnerability database