animated-css-kitnpm
animated-css-kit is a confirmed malicious npm package (MAL-2026-10432) that typosquats a legitimate package to trick installs (malicious versions 1.0.1, 1.0.3). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in animated-css-kit (npm)
What this malware does
The package presents itself as a PostCSS plugin for animate.css, but its main export (src/plugin.js createPlugin) synchronously triggers src/side-effects.js, which is heavily obfuscated (obfuscator.io string-array with RC4 decoding, anti-debug via Function.prototype.toString inspection, console-method hijacking) while the rest of the src/*.js tree is plain unobfuscated PostCSS code. The obfuscated module fetches a remote JSON payload, base64-decodes its message field, and executes it via new Function('require', m)(require), handing the caller's require to attacker-supplied code with retry-up-to-10-times logic. This fires when a consumer imports the package and instantiates the exported plugin (the documented usage in a build pipeline), giving the attacker arbitrary code execution on the installer/build machine with full access to the surrounding Node.js environment. The clean plugin surface + targeted obfuscation of only the network-and-eval module + evocative name mimicking the animate.css ecosystem are consistent with a supply-chain attack using a cover-story package.
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
Scan your lockfiles (package-lock.json, pnpm-lock.yaml, yarn.lock, requirements.txt, poetry.lock, etc.) and build artifacts for animated-css-kit (2 malicious versions). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging animated-css-kit across your stack and pipelines.
If you installed it — respond
animated-css-kit is a typosquat — you almost certainly intended a legitimately-named package. Remove animated-css-kit, 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 animated-css-kit was ever installed, its post-install/runtime payload may have already executed. O3's L7 egress monitoring and runtime eBPF sensors detect the credential exfiltration or command-and-control callback after install and block the malicious outbound channel, so you catch and contain the actual compromise — not just the presence of the package.
How O3 protects you
O3 blocks animated-css-kit before install through its supply-chain scanner, and if it has already run, detects and severs the exfiltration or C2 callback at runtime through L7 egress monitoring and eBPF.
Frequently asked questions
Campaign
References
Credits
- Amazon Inspector · finder
Detect & block this
O3 blocks animated-css-kit-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.