MAL-2026-10048 Malicious code in chai-as-thread (npm)
- Package
- chai-as-thread
- Registry
- npm
What is MAL-2026-10048?
MAL-2026-10048 is a malicious package in chai-as-thread, published on 9 Jul 2026.
Official description
On require, the package spawns a detached node child that runs lib/initializeCaller.js. That script decodes a base64-obscured URL (https://tomato-brunhilda-40.tiiny.site/index.json) and base64-obscured header credentials, fetches JSON from the endpoint via axios, and executes the returned cookie field with full require access using new Function.constructor("require", response)(require). The remote host is an anonymous tiiny.site subdomain that can serve arbitrary code at any time. The package name mimics chai-as-promised and the README impersonates the pino logger project, indicating a typosquat lure delivering a remote-code-execution dropper.
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.
What should I do about MAL-2026-10048?
Remove the package from your dependencies and lockfiles, then rotate any secrets on machines where it was installed.
Sources
Also known as GHSA-pjgc-4vf2-4cj7.