Which versions of kazumarii-kyuuna are malicious?

The following npm versions of kazumarii-kyuuna are flagged malicious: 1.0.23, 1.0.24. Treat any of these as compromised.

How do I remediate kazumarii-kyuuna if I installed it?

Remove kazumarii-kyuuna 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 kazumarii-kyuuna — how do I know if it already compromised me?

If kazumarii-kyuuna 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 kazumarii-kyuuna across my projects, lockfiles, and CI pipelines?

Search your lockfiles and build artifacts for kazumarii-kyuuna (2 malicious versions).

Malicious package

kazumarii-kyuunanpm

Advisory published Oct 27, 2026Updated Nov 9, 2026

kazumarii-kyuuna is a confirmed malicious npm package (MAL-2026-18982) that executes malicious code on install (malicious versions 1.0.23, 1.0.24). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in kazumarii-kyuuna (npm)

MAL-2026-18982

Immediate action

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

npm uninstall kazumarii-kyuuna

What this malware does

kazumarii-kyuuna is a fork of the Baileys WhatsApp Web library that silently subscribes the installer's own WhatsApp account to WhatsApp Channels chosen by the publisher. When the socket connects, code in lib/Socket/newsletter.js sends the WhatsApp w:mex FOLLOW query for the channel ID(s) 120363421930637018@newsletter, 120363422166977077@newsletter, 120363426326511354@newsletter, using the victim's authenticated session and without telling them. Same behaviour as the PhantomSub family (MAL-2026-17342).

Malicious versions

2 flagged

1.0.231.0.24

Detection & response playbook

Malicious package

Find it
Search your lockfiles and build artifacts for kazumarii-kyuuna (2 malicious versions).
If you installed it — respond
Remove kazumarii-kyuuna 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 kazumarii-kyuuna 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. kazumarii-kyuuna on npm has been identified as a malicious package (versions 1.0.23, 1.0.24 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

References

Credits

CyberXYZ · finder

Detect & block this

O3 blocks kazumarii-kyuuna-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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