# chai-mocks (npm) malicious package — MAL-2026-5306 | O3 Security

Malicious package

# chai-mocksnpm

chai-mocks is a confirmed malicious npm package (MAL-2026-5306) that opens a backdoor for remote access (malicious version 1.1.5). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in chai-mocks (npm)

MAL-2026-5306

Immediate action

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

npm uninstall chai-mocks

## What this malware does

The package masquerades as a pino-style logger middleware but is a remote code loader. When the exported middleware is invoked, index.js spawns a detached `node./lib/caller.js` child process. caller.js fetches [https://jsonkeeper.com/b/U2BTS](https://jsonkeeper.com/b/U2BTS) (with a second URL [https://jsonkeeper.com/b/XRGF3](https://jsonkeeper.com/b/XRGF3) stored base64-encoded in a variable named DEV\_API\_KEY to disguise it as a configuration constant), reads the `cookie` field of the JSON response, and executes it via `new Function.constructor('require', s)(require)` — arbitrary attacker-controlled code execution with full Node `require` access on the consumer's machine. jsonkeeper.com is an anonymous, mutable paste service; the contents can be changed by the author at any time without republishing the package. The package name (`chai-mocks`) and bait API surface (exports `pino`, references DEFAULT\_LEVELS/redact/customLevels, scripts named `smoke:pino`) are unrelated to the package's author identity (Alexus111 [hello@jsonspack.com](mailto:hello@jsonspack.com)) and are designed to lure developers who mistype or confuse it with the chai or pino logger ecosystems. The base64-obfuscated URLs and fake `DEV_API_KEY`/`DEV_SECRET_KEY` variable names confirm intent to hide the C2 endpoint.

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.

## Malicious versions

1 flagged

1.1.5

## Indicators of compromise (SHA-256)

2110c382b534a2754972e66578b044823108410f3a656aad1616834d18bba322

e65359853241724a1b519599469dadfcd2b32674455db9fe5284cb7553a5ddf4

## Detection & response playbook

Backdoor / remote access

1.  ### Find it
    
    Scan your lockfiles (package-lock.json, pnpm-lock.yaml, yarn.lock, requirements.txt, poetry.lock, etc.) and build artifacts for chai-mocks (version 1.1.5). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging chai-mocks across your stack and pipelines.
    
2.  ### If you installed it — respond
    
    chai-mocks 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.
    
3.  ### Did it already run?
    
    If chai-mocks 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.
    
4.  ### How O3 protects you
    
    O3 blocks chai-mocks 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-mocks on npm has been identified as a malicious package (version 1.1.5 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

## Campaign

GHSA-5wqh-hxqx-c6j3IN-MAL-2026-006086

## References

-   [github.com](https://github.com/advisories/GHSA-5wqh-hxqx-c6j3)
-   [npmjs.com](https://www.npmjs.com/package/chai-mocks/v/1.1.5)

## Credits

-   Amazon Inspector · finder

## Detect & block this

O3 blocks chai-mocks\-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](/malware-detection) [Runtime egress monitoring](/egress-monitor)

## Explore

[All malware advisories](/malware) [How O3 detects malware](/malware-database) [Vulnerability database](/vulnerability)