nottuff4npm
nottuff4 is a confirmed malicious npm package (MAL-2026-5917) that opens a backdoor for remote access (malicious versions 1.1.7, 1.7.7, 2.0.0). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in nottuff4 (npm)
What this malware does
Package ships a Scramjet-based web proxy (sw.js service worker + bare-mux + WASM rewriter under assets/) plus a static 'Riverbend Tutoring' index.html cover page. index.html lines 60-69 install click/keydown/touchstart listeners that call window.open("https://abdct.com/", "_blank", "noreferrer") on first user interaction. The package is one of ~85 throwaway sibling names auto-published via the bundled auto-publish.sh (imillegal*, ishowfeet*, nottuff*, abuden*, ratelimitsucks*); package.json carries placeholder metadata (name 'package', empty author, no homepage/repo). The asset JavaScript is heavily obfuscated (hex-mangled identifiers throughout assets/*.js), consistent with the upstream Scramjet bundles. main is set to sw.js, which begins with importScripts('./8cfc2/hgshm.js') and uses service-worker globals (self.addEventListener for install/activate/fetch/message); require('nottuff4') from Node throws on the first line, so there is no install-time or import-time code path that executes against a developer who runs npm install nottuff4. The harm — namespace pollution, ToS-evading proxying, and the monetized popup redirect — only materializes when someone unpacks the tarball and serves it as a website to browser visitors. Routing for human review as registry-policy abuse rather than as a supply-chain attack on installers.
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 nottuff4 (3 malicious versions). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging nottuff4 across your stack and pipelines.
If you installed it — respond
nottuff4 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 nottuff4 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 nottuff4 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 nottuff4-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the C2 callback and severs the channel.