What does the karem4 malware do?

The package karem4 was found to contain malicious code. The OpenSSF Package Analysis project identified 'karem4' @ 1.0.0 (npm) as malicious. It is considered malicious because: - The package communicates with a domain associated with malicious activity. - The package executes one or more commands associated with malicious behavior.

Which versions of karem4 are malicious?

The following npm versions of karem4 are flagged malicious: 1.0.0. Treat any of these as compromised.

How do I remediate karem4 if I installed it?

Remove karem4 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 karem4 — how do I know if it already compromised me?

If karem4 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 karem4 across my projects, lockfiles, and CI pipelines?

Search your lockfiles and build artifacts for karem4 (version 1.0.0).

Malicious package

karem4npm

Advisory published Dec 3, 2025Updated Dec 3, 2025

karem4 is a confirmed malicious npm package (MAL-2025-191960) that executes malicious code on install (malicious version 1.0.0). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in karem4 (npm)

MAL-2025-191960

Immediate action

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

npm uninstall karem4

What this malware does

The package karem4 was found to contain malicious code.

The OpenSSF Package Analysis project identified 'karem4' @ 1.0.0 (npm) as malicious.

It is considered malicious because:

The package communicates with a domain associated with malicious activity.
The package executes one or more commands associated with malicious behavior.

Malicious versions

1 flagged

1.0.0

Indicators of compromise (SHA-256)

b843a0d849da7453ce803b77a117a501a3b1e4b04eae8222d3b59d48438931cc

5a1d3bd676881934532a2e75fd644e22b2e4f26fb08bde6d48ff6d529de7467d

Detection & response playbook

Malicious package

Find it
Search your lockfiles and build artifacts for karem4 (version 1.0.0).
If you installed it — respond
Remove karem4 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 karem4 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. karem4 on npm has been identified as a malicious package (version 1.0.0 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Credits

Amazon Inspector · finder
OpenSSF: Package Analysis · finder

Detect & block this

O3 blocks karem4-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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