Which versions of kcheck are malicious?

The following npm versions of kcheck are flagged malicious: 7.0.0, 8.0.0. Treat any of these as compromised.

How do I remediate kcheck if I installed it?

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

If kcheck was ever installed, its post-install/runtime payload may have already executed. O3's L7 egress monitoring and runtime eBPF sensors detect the credential exfiltration or command-and-control callback after install and block the malicious outbound channel, so you catch and contain the actual compromise — not just the presence of the package.

Is kcheck part of a known attack campaign?

Yes — kcheck is associated with the GHSA-rw58-vpg4-jcpx 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 kcheck across my projects, lockfiles, and CI pipelines?

Scan your lockfiles (package-lock.json, pnpm-lock.yaml, yarn.lock, requirements.txt, poetry.lock, etc.) and build artifacts for kcheck (2 malicious versions). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging kcheck across your stack and pipelines.

Malicious package

kchecknpm

Malicious code in kcheck (npm) Remove it immediately and rotate any exposed credentials.

MAL-2025-192960

Immediate action

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

npm uninstall kcheck

What this malware does

The package kcheck was found to contain malicious code.

Any computer that has this package installed or running should be considered fully compromised. All secrets and keys stored on that computer should be rotated immediately from a different computer. The package should be removed, but as full control of the computer may have been given to an outside entity, there is no guarantee that removing the package will remove all malicious software resulting from installing it.

The OpenSSF Package Analysis project identified 'kcheck' @ 7.0.0 (npm) as malicious.

It is considered malicious because:

The package communicates with a domain associated with malicious activity.

Malicious versions

2 flagged

7.0.08.0.0

Indicators of compromise (SHA-256)

acbe3cbc8265818f916b6b3b01a495c32b76836970ccb046ba1d0922da7036b2

e7a00be4be3bf4e3344c38d3f3f597170f3df9c89402f2716c2867eb65b14ddf

660a47461992421159d386fb5e8ce14c3c794e8059b276d4de539ca2235d8780

9666f7f55b90b84ee1e458016ed3eb475f26465bcf2d4fbe690a142c3a53e311

Detection & response playbook

Malicious package

Find it
Scan your lockfiles (package-lock.json, pnpm-lock.yaml, yarn.lock, requirements.txt, poetry.lock, etc.) and build artifacts for kcheck (2 malicious versions). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging kcheck across your stack and pipelines.
If you installed it — respond
Remove kcheck 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 kcheck was ever installed, its post-install/runtime payload may have already executed. O3's L7 egress monitoring and runtime eBPF sensors detect the credential exfiltration or command-and-control callback after install and block the malicious outbound channel, so you catch and contain the actual compromise — not just the presence of the package.
How O3 protects you
O3 blocks kcheck before install through its supply-chain scanner, and if it has already run, detects and severs the exfiltration or C2 callback at runtime through L7 egress monitoring and eBPF.

Frequently asked questions

No. kcheck on npm has been identified as a malicious package (versions 7.0.0, 8.0.0 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

GHSA-rw58-vpg4-jcpx

References

github.com

Credits

Amazon Inspector · finder
OpenSSF: Package Analysis · finder

Detect & block this

O3 blocks kcheck-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