chain-chai-asyncnpm
Advisory published Updated
chain-chai-async is a confirmed malicious npm package (MAL-2026-10055) that typosquats a legitimate package to trick installs (malicious version 1.3.5). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in chain-chai-async (npm)
What this malware does
[email protected] impersonates the pino logging library (README badge links to npm/pino, exports module.exports.pino = middleware, and ships files copied from the real pino source tree). Its exported middleware factory in index.js spawns lib/caller.js as a detached child node process with stdio ignored, decoupling the payload from the parent's lifecycle and suppressing its output. lib/caller.js issues an HTTPS GET to https://jsonkeeper.com/b/EXSIF, extracts the cookie field from the JSON response, and passes it to new Function.constructor('require', s)(require) — executing attacker-controlled JavaScript with full Node require access on any machine that loads and invokes the package. The remote source is a mutable, unauthenticated paste service, so the executed code can be swapped at any time by the attacker without republishing the package. Any consumer who installs this package believing it to be pino and calls its exported middleware will trigger arbitrary remote code execution on the host.
Malicious versions
Indicators of compromise (SHA-256)
Detection & response playbook
TyposquatFind it
Search your lockfiles and build artifacts for chain-chai-async (version 1.3.5).
If you installed it — respond
chain-chai-async is a typosquat — you almost certainly intended a legitimately-named package. Remove chain-chai-async, 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 chain-chai-async 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 chain-chai-async-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.