chai-as-benchnpm
chai-as-bench is a confirmed malicious npm package (MAL-2026-13699) that steals credentials and exfiltrates sensitive data (malicious version 7.0.3). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in chai-as-bench (npm)
What this malware does
The package presents itself as a chai plugin (name resembles chai-as-promised, manifest description references chai assertions), but ships no chai-related functionality. index.js unconditionally loads lib/config.js on require(), and lib/config.js is a ~4 MB obfuscator.io payload with a 23,890-entry rotating string array, hex-obfuscated identifiers, and control-flow flattening. The remaining lib/ files (proto.js, multistream.js, transport.js) plus LICENSE are copied verbatim from the unrelated pino logger project as camouflage, and index.js itself only exports a no-op Express-style middleware ((_req,_res,next)=>next()). README contains placeholder yourusername GitHub URLs and generic author metadata ([email protected]). Heavy obfuscation of a multi-megabyte payload that runs on every require(), inside a package whose advertised purpose does not require any such code and whose surrounding files are stolen from an unrelated project, is the standard loader/stealer shape for an npm supply-chain plant targeting developers who mistype chai-as-promised.
Malicious versions
Indicators of compromise (SHA-256)
Detection & response playbook
Credential / info stealerFind it
Scan your lockfiles (package-lock.json, pnpm-lock.yaml, yarn.lock, requirements.txt, poetry.lock, etc.) and build artifacts for chai-as-bench (version 7.0.3). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging chai-as-bench across your stack and pipelines.
If you installed it — respond
chai-as-bench is built to steal secrets, so assume every credential the build or runtime could read is compromised. Remove it from your project and lockfile, then rotate ALL exposed secrets — npm/registry tokens, cloud keys, CI/CD secrets, SSH keys, and any .env values — from a known-clean machine. Audit logs for unauthorized use of those credentials.
Did it already run?
If chai-as-bench 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-bench 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
Campaign
References
Credits
- Amazon Inspector · finder
Detect & block this
O3 blocks chai-as-bench-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the credential exfiltration and severs the channel.