eslint-plusnpm
eslint-plus is a confirmed malicious npm package (MAL-2026-10087) that typosquats a legitimate package to trick installs (malicious versions 6.0.4, 6.0.5). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in eslint-plus (npm)
What this malware does
Package declares postinstall: node lib/utils/index.js, which spawns a detached, stdio-suppressed Node child (spawn with detached:true, stdio:'ignore', child.unref()) that runs lib/utils/smtp-connection/index.js. That script uses axios to GET https://jsonkeeper.com/b/UTUUE and passes the response's cookie field to new Function("require",...)(require), executing whatever JavaScript the anonymous mutable paste currently returns with full Node privileges on the installer's machine. jsonkeeper.com is a public, anonymously-editable JSON paste service, so the executed code can be silently swapped by the operator at any time. The detach + stdio-ignore + unref pattern is designed to survive after npm install exits and to hide output from the installer. Separately, the package is named eslint-plus and its homepage/description reference React Training and eslint tooling, but main points at lib/nodemailer.js and the tarball ships a copied nodemailer source tree authored by 'Andris Reinman' — a namespace/impersonation cover for the dropper.
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 eslint-plus (2 malicious versions). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging eslint-plus across your stack and pipelines.
If you installed it — respond
eslint-plus is a typosquat — you almost certainly intended a legitimately-named package. Remove eslint-plus, 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 eslint-plus 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 eslint-plus 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 eslint-plus-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.