Which versions of modustack are malicious?

The following npm versions of modustack are flagged malicious: 1.0.1, 1.0.3, 1.0.4. Treat any of these as compromised.

How do I remediate modustack if I installed it?

Remove modustack from your project and lockfile, then assume any secrets accessible to the build or runtime were exposed: rotate API keys, tokens, and credentials, and audit for unexpected outbound activity or persistence.

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

If modustack 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 modustack part of a known attack campaign?

Yes — modustack is associated with the RLMA-2026-05163, RLUA-2026-06330 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 modustack across my projects, lockfiles, and CI pipelines?

Search your lockfiles and build artifacts for modustack (3 malicious versions).

Malicious package

modustacknpm

Advisory published Jul 7, 2026Updated Sep 1, 2026

modustack is a confirmed malicious npm package (MAL-2026-7321) that executes malicious code on install (malicious versions 1.0.1, 1.0.3, 1.0.4). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in modustack (npm)

MAL-2026-7321

Immediate action

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

npm uninstall modustack

Malicious versions

3 flagged

1.0.11.0.31.0.4

Indicators of compromise (SHA-256)

e0eb74bfb9e03777f79ee0da0f64a893c900c3065057b003bec6566885b6fa41

6963ac1de12575fdf68e8d0ea164fde62975c849cde460bbe6c3dffe51e19565

Detection & response playbook

Malicious package

Find it
Search your lockfiles and build artifacts for modustack (3 malicious versions).
If you installed it — respond
Remove modustack from your project and lockfile, then assume any secrets accessible to the build or runtime were exposed: rotate API keys, tokens, and credentials, and audit for unexpected outbound activity or persistence.
Did it already run?
If modustack 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. modustack on npm has been identified as a malicious package (versions 1.0.1, 1.0.3, 1.0.4 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

RLMA-2026-05163RLUA-2026-06330

References

github.com

Credits

ReversingLabs · finder

Detect & block this

O3 blocks modustack-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the malicious outbound activity and severs the channel.

Malware detection Runtime egress monitoring

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