Which versions of whs4_deu are malicious?

The following npm versions of whs4_deu are flagged malicious: 1.0.0, 1.0.1. Treat any of these as compromised.

How do I remediate whs4_deu if I installed it?

whs4_deu establishes remote access, so treat any host that installed it as fully compromised. Isolate the machine, remove the package, rotate all credentials it could reach, and rebuild from a trusted image rather than cleaning in place — a backdoor may have planted additional persistence.

I already installed whs4_deu — how do I know if it already compromised me?

If whs4_deu 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 whs4_deu part of a known attack campaign?

Yes — whs4_deu is associated with the IN-MAL-2026-011219, IN-MAL-2026-017377 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 whs4_deu across my projects, lockfiles, and CI pipelines?

Search your lockfiles and build artifacts for whs4_deu (2 malicious versions).

Malicious package

whs4_deunpm

Advisory published Jul 25, 2026Updated Aug 11, 2026

whs4_deu is a confirmed malicious npm package (MAL-2026-11070) that opens a backdoor for remote access (malicious versions 1.0.0, 1.0.1). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in whs4_deu (npm)

MAL-2026-11070

Immediate action

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

npm uninstall whs4_deu

What this malware does

package.json declares a postinstall hook that runs index.js on npm install. On execution, index.js POSTs the installer's absolute __filename path (which typically embeds the OS username and directory layout), Node.js version, and platform/architecture to a hardcoded Discord webhook at discord.com/api/webhooks/1530599209269465319/. The destination is not caller-configurable, the behavior is undocumented, and the webhook URL literal is split via string concatenation to evade trivial grep for the full endpoint. The package ships no other functionality consistent with its name; the install-time beacon is the sole observable behavior.

The OpenSSF Package Analysis project identified 'whs4_deu' @ 1.0.1 (npm) as malicious.

It is considered malicious because:

The package communicates with a domain associated with malicious activity.

Malicious versions

2 flagged

1.0.01.0.1

Indicators of compromise (SHA-256)

96d7709dc56eae4bfe07031da42425b4a94a169255cd7b3bde0f31f0516e0fb0

5cb5c50b57f755039aeebab19cba308fd86dad10eddad29a94ab09396fdfe6f5

2d5a7dc2cf8fe83229aec6f45e6008ce2b353039a87607b930eb44928f97538c

Detection & response playbook

Backdoor / remote access

Find it
Search your lockfiles and build artifacts for whs4_deu (2 malicious versions).
If you installed it — respond
whs4_deu establishes remote access, so treat any host that installed it as fully compromised. Isolate the machine, remove the package, rotate all credentials it could reach, and rebuild from a trusted image rather than cleaning in place — a backdoor may have planted additional persistence.
Did it already run?
If whs4_deu 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. whs4_deu on npm has been identified as a malicious package (versions 1.0.0, 1.0.1 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

IN-MAL-2026-011219IN-MAL-2026-017377

References

Credits

Amazon Inspector · finder
OpenSSF: Package Analysis · finder

Detect & block this

O3 blocks whs4_deu-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the C2 callback and severs the channel.

Malware detection Runtime egress monitoring

Explore

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