Which versions of chai-jsonss are malicious?

The following npm versions of chai-jsonss are flagged malicious: 3.7.7. Treat any of these as compromised.

How do I remediate chai-jsonss if I installed it?

Remove chai-jsonss 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 chai-jsonss — how do I know if it already compromised me?

If chai-jsonss 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 chai-jsonss part of a known attack campaign?

Yes — chai-jsonss is associated with the IN-MAL-2026-017246 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 chai-jsonss 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 chai-jsonss (version 3.7.7). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging chai-jsonss across your stack and pipelines.

Malicious package

chai-jsonssnpm

chai-jsonss is a confirmed malicious npm package (MAL-2026-13692) that executes malicious code on install (malicious version 3.7.7). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in chai-jsonss (npm)

MAL-2026-13692

Immediate action

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

npm uninstall chai-jsonss

What this malware does

On import, index.js invokes postCallers() which resolves a base64-encoded URL stored in lib/const.js (decoding to https://1uznbx.s.gy/7xdQmt), GETs the response via axios, base64-decodes response.data.model, and passes it to new Function(require) — executing attacker-controlled JavaScript in-process. The destination is hidden as a DEV_API_KEY field on a fake process.env-shaped local module, and the payload URL is a shortlink to a mutable remote resource. The package name resembles chai but its main entry contains no chai-related functionality; the only import-time behavior is fetch-and-eval of remote code.

Malicious versions

1 flagged

3.7.7

Indicators of compromise (SHA-256)

3b1fff32102bc74783cae571646ec0fd68b14c614b35a63badd814a64caa3b67

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 chai-jsonss (version 3.7.7). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging chai-jsonss across your stack and pipelines.
If you installed it — respond
Remove chai-jsonss 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 chai-jsonss 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 chai-jsonss 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. chai-jsonss on npm has been identified as a malicious package (version 3.7.7 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

IN-MAL-2026-017246

References

npmjs.com

Credits

Amazon Inspector · finder

Detect & block this

O3 blocks chai-jsonss-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

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