Which versions of express-plugin are malicious?

The following npm versions of express-plugin are flagged malicious: 1.6.6. Treat any of these as compromised.

How do I remediate express-plugin if I installed it?

express-plugin 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 express-plugin — how do I know if it already compromised me?

If express-plugin 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 express-plugin part of a known attack campaign?

Yes — express-plugin is associated with the IN-MAL-2026-007607 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 express-plugin 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 express-plugin (version 1.6.6). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging express-plugin across your stack and pipelines.

Malicious package

express-pluginnpm

express-plugin is a confirmed malicious npm package (MAL-2026-6523) that steals credentials and exfiltrates sensitive data (malicious version 1.6.6). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in express-plugin (npm)

MAL-2026-6523

Immediate action

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

npm uninstall express-plugin

What this malware does

On module load, index.js auto-invokes initPlugin(), which HTTP-GETs https://jsonkeeper.com/b/PRA3O, parses the JSON response, and passes the response's cookie field to Function.constructor with require exposed, then immediately invokes the resulting function. Any process that does require('express-plugin') executes arbitrary JavaScript pulled from a mutable third-party paste host with full Node require privileges, giving the operator of that paste full control of the installer's machine. The file is headed as normalize-path (ES6 safe version) and exports an unused normalizePath function as decoy; the package name express-plugin is cover framing intended to make the package look like a benign Express middleware. The remote payload is attacker-mutable: today's content can be swapped for credential theft, persistence, or any other action at any time without republishing the package.

Malicious versions

1 flagged

1.6.6

Indicators of compromise (SHA-256)

183cda19ef38d3451b375669fb460577a83217091d96d7fc11d5bf33679c8003

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 express-plugin (version 1.6.6). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging express-plugin across your stack and pipelines.
If you installed it — respond
express-plugin 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 express-plugin 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 express-plugin 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. express-plugin on npm has been identified as a malicious package (version 1.6.6 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

IN-MAL-2026-007607

References

npmjs.com

Credits

Amazon Inspector · finder

Detect & block this

O3 blocks express-plugin-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

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