better-tailwindcssnpm
Advisory published Updated
better-tailwindcss is a confirmed malicious npm package (MAL-2026-10550) that executes malicious code on install (malicious version 4.6.3). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in better-tailwindcss (npm)
What this malware does
The package publishes under the name of the legitimate better-tailwindcss project but its package.json declares both a runtime and dev dependency on better-tailwindcss resolved from http://pack.nppacks.com/npm/better-tailwindcss — a plain-HTTP, non-registry host with no integrity hash and no TLS. On npm install, npm fetches and installs that arbitrary, mutable tarball, and any install/postinstall scripts inside it execute on the installer's machine. The shipped code itself is a Babel plugin clone unrelated to the real better-tailwindcss project (a tailwind ESLint plugin) and carries a self-label describing the package as being for 'Security Research Testing Purpose,' confirming it is a namespace squat used as a delivery vehicle for code hosted at pack.nppacks.com.
Malicious versions
Indicators of compromise (SHA-256)
Detection & response playbook
Malicious packageFind it
Search your lockfiles and build artifacts for better-tailwindcss (version 4.6.3).
If you installed it — respond
Remove better-tailwindcss from your project and lockfile, then assume any secrets accessible to the build or runtime were exposed: rotate API keys, tokens, and credentials, and audit for unexpected outbound activity or persistence.
Did it already run?
If better-tailwindcss 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 better-tailwindcss-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.