Which versions of chai-as-buffered are malicious?

The following npm versions of chai-as-buffered are flagged malicious: 3.7.24. Treat any of these as compromised.

How do I remediate chai-as-buffered if I installed it?

chai-as-buffered establishes remote access, so treat any host that installed it as fully compromised. Isolate the machine, remove the package, rotate all credentials it could reach, and rebuild from a trusted image rather than cleaning in place — a backdoor may have planted additional persistence.

I already installed chai-as-buffered — how do I know if it already compromised me?

If chai-as-buffered 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-as-buffered part of a known attack campaign?

Yes — chai-as-buffered is associated with the IN-MAL-2026-009142 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-as-buffered 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-as-buffered (version 3.7.24). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging chai-as-buffered across your stack and pipelines.

Malicious package

chai-as-bufferednpm

Malicious code in chai-as-buffered (npm) Remove it immediately and rotate any exposed credentials.

MAL-2026-10041

Immediate action

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

npm uninstall chai-as-buffered

What this malware does

[email protected] is a typosquat lure (name resembles chai-as-promised; README and module exports impersonate the pino logger) whose actual behavior is a remote-payload dropper. lib/caller.js shadows process with a local object whose env holds base64-encoded constants for the C2 URL, header name, and header value, hiding the destination from review and from env scanning. When the exported middleware is invoked (e.g., via chai.use(...) or require('chai-as-buffered') wiring through the pino-styled export), the package base64-decodes the hidden URL (https://api.jsonstorage.net/v1/json/2ef8c758-a96f-459e-b036-b3b90379a165/a179ea35-b962-4722-b3f1-e28316d1a44a), spawns a detached, stdio-ignored node./lib/caller.js child, fetches a JSON document from that mutable third-party blob, and passes the document's cookie field to Function.constructor('require', s) invoked with the live require. The fetched JavaScript executes with full require access on the installer's machine. The destination is an attacker-controlled mutable JSON store whose content can be changed at any time, giving the publisher arbitrary code execution against any environment that loads this package.

Malicious versions

1 flagged

3.7.24

Indicators of compromise (SHA-256)

3d136202d96267459c4bf3aaaf6c903d7bd2c491901b61dcf2f391a4612f951a

Detection & response playbook

Backdoor / remote access

Find it
Scan your lockfiles (package-lock.json, pnpm-lock.yaml, yarn.lock, requirements.txt, poetry.lock, etc.) and build artifacts for chai-as-buffered (version 3.7.24). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging chai-as-buffered across your stack and pipelines.
If you installed it — respond
chai-as-buffered establishes remote access, so treat any host that installed it as fully compromised. Isolate the machine, remove the package, rotate all credentials it could reach, and rebuild from a trusted image rather than cleaning in place — a backdoor may have planted additional persistence.
Did it already run?
If chai-as-buffered 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-as-buffered 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-as-buffered on npm has been identified as a malicious package (version 3.7.24 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

IN-MAL-2026-009142

References

npmjs.com

Credits

Amazon Inspector · finder

Detect & block this

O3 blocks chai-as-buffered-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the C2 callback and severs the channel.

Malware detection Runtime egress monitoring