event-hunternpm
event-hunter is a confirmed malicious npm package (MAL-2026-16478) 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 event-hunter (npm)
What this malware does
On npm install, the declared postinstall hook runs node index.js, which reads os.hostname() and a timestamp, base64-encodes the JSON payload, and issues an HTTPS GET to https://estimator-nemeses-unwatched.ngrok-free.dev/canary?d=<base64>. The destination is a hardcoded ngrok tunnel unrelated to any registry or vendor infrastructure, and the beacon fires automatically without any caller action or opt-in. The package's own metadata describes it as a Dependency Confusion to RCE proof-of-concept, and the install-time callback carries the installer's internal hostname to an external third party.
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 event-hunter (version 1.0.0). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging event-hunter across your stack and pipelines.
If you installed it — respond
event-hunter 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 event-hunter 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 event-hunter 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 event-hunter-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the C2 callback and severs the channel.