chai-as-polishednpm
Advisory published Updated
chai-as-polished is a confirmed malicious npm package (MAL-2026-5901) that typosquats a legitimate package to trick installs (malicious version 7.0.8). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in chai-as-polished (npm)
What this malware does
Package name is a one-edit typosquat of the widely-used chai-as-promised, but the shipped code is unrelated to chai. The exported middleware spawns a detached, unref'd child process running lib/initializeCaller.js. That file constructs a fake process.env containing three base64-encoded fields which decode to the URL https://tomato-brunhilda-40.tiiny.site/index.json and the header x-secret-key: _, fetches that URL via axios, and passes response.data.cookie to new Function.constructor('require', response)(require) — executing arbitrary attacker-supplied JavaScript with the installer's Node require available. The base64 staging of the URL and header has no functional purpose other than to hide the destination from cursory review. tiiny.site is an anonymous static-hosting service whose contents the author can change at any time, so the executed payload is fully attacker-controlled and mutable. Triggering requires a consumer to invoke the package's middleware, which is the documented entry point for anyone deceived by the name into installing it.
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
Indicators of compromise (SHA-256)
Detection & response playbook
TyposquatFind it
Search your lockfiles and build artifacts for chai-as-polished (version 7.0.8).
If you installed it — respond
chai-as-polished is a typosquat — you almost certainly intended a legitimately-named package. Remove chai-as-polished, install the correct package, and rotate any secrets exposed during the install since post-install scripts may have already run.
Did it already run?
If chai-as-polished 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
Campaign
References
Credits
- Amazon Inspector · finder
- ReversingLabs · finder
Detect & block this
O3 blocks chai-as-polished-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.