Which versions of core-js-gns are malicious?

The following npm versions of core-js-gns are flagged malicious: 1.0.0. Treat any of these as compromised.

How do I remediate core-js-gns if I installed it?

core-js-gns 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 core-js-gns — how do I know if it already compromised me?

If core-js-gns 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 core-js-gns part of a known attack campaign?

Yes — core-js-gns is associated with the IN-MAL-2026-018256 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 core-js-gns across my projects, lockfiles, and CI pipelines?

Search your lockfiles and build artifacts for core-js-gns (version 1.0.0).

Malicious package

core-js-gnsnpm

core-js-gns is a confirmed malicious npm package (MAL-2026-14175) that steals credentials and exfiltrates sensitive data (malicious version 1.0.0). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in core-js-gns (npm)

MAL-2026-14175

Immediate action

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

npm uninstall core-js-gns

What this malware does

The package's postinstall hook (package.json → node init.js) runs an installer-side dropper. init.js gates on developer-machine heuristics (presence of Desktop/Documents/Downloads directories) and a 24-hour skip marker, then POSTs hostname, username, platform, architecture, Node version, OS release, and package name/version to https://core-js-buffer.domaup-com.workers.dev/report. It then HTTP GETs an AES-256-GCM ciphertext from the same host with TLS verification disabled (rejectUnauthorized: false), decrypts it with a key derived from a hardcoded seed, checks the plaintext contains the cover-story string TelemetrySender, writes the result to ~/.cache/core-js-buffer/modules/runtime.py, and spawns Python detached (stdio:'ignore', .unref()) to execute it. The package name mimics the legitimate core-js library. Behavior is arbitrary remote code execution on the installer's machine, fetched from an attacker-controlled endpoint at npm install time, preceded by installer identifier exfiltration to the same endpoint.

Malicious versions

1 flagged

1.0.0

Indicators of compromise (SHA-256)

ae5eadad92952db436b03dd9673b34d203d9296b0913389de2aa0d9fef441631

Detection & response playbook

Credential / info stealer

Find it
Search your lockfiles and build artifacts for core-js-gns (version 1.0.0).
If you installed it — respond
core-js-gns 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 core-js-gns 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. core-js-gns 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-2026-018256

References

npmjs.com

Credits

Amazon Inspector · finder

Detect & block this

O3 blocks core-js-gns-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