express-mocha-testnpm
Advisory published Updated
express-mocha-test is a confirmed malicious npm package (MAL-2026-6568) that typosquats a legitimate package to trick installs (malicious version 0.0.1). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in express-mocha-test (npm)
What this malware does
[email protected] declares a postinstall lifecycle hook that loads the package's main module, which calls fetch() against an anonymous ngrok-free.app tunnel (https://2939e69fc408.ngrok-free.app/stats) and passes the response body directly to eval(). This executes attacker-controlled JavaScript on any machine that runs npm install for this package, with no pinning, integrity check, or scoping. The destination is an ephemeral, mutable, attacker-operated tunnel — not a registry, not a publisher domain. Package metadata impersonates well-known maintainers of the express and mocha projects (author field set to 'TJ Holowaychuk'), and the stated description ('Integrate redis with cookies') does not match the shipped behavior, indicating deliberate impersonation rather than misconfiguration.
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.
The OpenSSF Package Analysis project identified 'express-mocha-test' @ 0.0.1 (npm) as malicious.
It is considered malicious because:
- The package communicates with a domain associated with malicious activity.
Malicious versions
Indicators of compromise (SHA-256)
Detection & response playbook
TyposquatFind it
Search your lockfiles and build artifacts for express-mocha-test (version 0.0.1).
If you installed it — respond
express-mocha-test is a typosquat — you almost certainly intended a legitimately-named package. Remove express-mocha-test, 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 express-mocha-test 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
- OpenSSF: Package Analysis · finder
Detect & block this
O3 blocks express-mocha-test-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.