Which versions of libxmlussr are malicious?

Every published version of libxmlussr on npm is considered malicious. Remove the package entirely.

How do I remediate libxmlussr if I installed it?

Remove libxmlussr 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 libxmlussr — how do I know if it already compromised me?

If libxmlussr 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.

How do I find libxmlussr across my projects, lockfiles, and CI pipelines?

Search your lockfiles and build artifacts for libxmlussr (all published versions).

Malicious package

libxmlussrnpm

Advisory published Dec 11, 2025Updated Dec 11, 2025

libxmlussr is a confirmed malicious npm package (MAL-2025-192463) that executes malicious code on install. Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in libxmlussr (npm)

MAL-2025-192463

Immediate action

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

npm uninstall libxmlussr

What this malware does

The package libxmlussr was found to contain malicious code.

Malicious versions

all versions

Every published version of this package is considered malicious — remove it entirely.

Indicators of compromise (SHA-256)

2d94a22bb719650fe5b9629ed1918677f55f3a0719b015bd7851920bd36fbb05

Detection & response playbook

Malicious package

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

Credits

Amazon Inspector · finder

Detect & block this

O3 blocks libxmlussr-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

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