Which versions of winstem-logging are malicious?

The following npm versions of winstem-logging are flagged malicious: 1.0.1. Treat any of these as compromised.

How do I remediate winstem-logging if I installed it?

Remove winstem-logging 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 winstem-logging — how do I know if it already compromised me?

If winstem-logging 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 winstem-logging part of a known attack campaign?

Yes — winstem-logging is associated with the RLMA-2025-05199, RLUA-2025-06001 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 winstem-logging across my projects, lockfiles, and CI pipelines?

Search your lockfiles and build artifacts for winstem-logging (version 1.0.1).

Malicious package

winstem-loggingnpm

Advisory published Sep 26, 2025Updated Dec 2, 2025

winstem-logging is a confirmed malicious npm package (MAL-2025-47743) that executes malicious code on install (malicious version 1.0.1). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in winstem-logging (npm)

MAL-2025-47743

Immediate action

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

npm uninstall winstem-logging

Malicious versions

1 flagged

1.0.1

Indicators of compromise (SHA-256)

ce03a0128e0148a9585b8dbad3a6264494fa569586816730df3d7821549be304

8984a5e4ac11e8c2fc3e2ea0aed177139bf9d0741d8b407ae1b0a013721616a4

Detection & response playbook

Malicious package

Find it
Search your lockfiles and build artifacts for winstem-logging (version 1.0.1).
If you installed it — respond
Remove winstem-logging 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 winstem-logging 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. winstem-logging on npm has been identified as a malicious package (version 1.0.1 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

RLMA-2025-05199RLUA-2025-06001

References

Credits

Amazon Inspector · finder
ReversingLabs · finder

Detect & block this

O3 blocks winstem-logging-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

Explore

All malware advisories How O3 detects malware Vulnerability database