vite-plugin-compress-jsnpm
vite-plugin-compress-js is a confirmed malicious npm package (MAL-2026-5713) that opens a backdoor for remote access (malicious versions 0.5.5, 0.5.6, 0.5.7). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in vite-plugin-compress-js (npm)
What this malware does
On module load, this Vite plugin performs an HTTP GET to https://www.jsonkeeper.com/b/XVHGD (an anonymous, mutable paste host) and passes the response's data field to new Function.constructor("require",...), then invokes the resulting function with require — granting the remote payload full Node.js capabilities (fs, child_process, network) inside the consumer's Vite build process. dist/index.mjs (lines ~124-128) calls the fetch+eval directly via initPlugin(); dist/index.cjs (lines ~130-141) wraps the same payload in if (isMainThread) { new Worker(__filename) } else { initPlugin() }, spawning a worker that re-loads the module with isMainThread=false and executes the network-fetched code in the worker thread to obscure the behavior from naive inspection. The package name and metadata (author 'Vben', debug name 'vite-plugin-compression', plugin name 'vite:compression') clone the well-known vite-plugin-compress / vite-plugin-compression packages, and an otherwise-unused request dependency exists solely to perform the C2 fetch. Any developer or build system that imports this package executes whatever JavaScript the operator currently has hosted at the jsonkeeper paste.
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
Scan your lockfiles (package-lock.json, pnpm-lock.yaml, yarn.lock, requirements.txt, poetry.lock, etc.) and build artifacts for vite-plugin-compress-js (3 malicious versions). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging vite-plugin-compress-js across your stack and pipelines.
If you installed it — respond
vite-plugin-compress-js 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 vite-plugin-compress-js 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 vite-plugin-compress-js 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 vite-plugin-compress-js-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the C2 callback and severs the channel.