npm-sandbox-research-c5d6npm
npm-sandbox-research-c5d6 is a confirmed malicious npm package (MAL-2026-5760) that steals credentials and exfiltrates sensitive data (malicious version 1.0.0). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in npm-sandbox-research-c5d6 (npm)
What this malware does
The package declares a postinstall hook ("postinstall": "node run.js") that executes automatically on npm install. The shipped beacon scripts (beacon11.js, beacon_linux.js) load child_process, os, and http, read host identifiers via os.hostname() and os.platform(), and issue outbound HTTP GET/POST requests carrying that data. This is the install-time host-fingerprinting and exfiltration shape: lifecycle execution + system-info collection + outbound network in a single chain, with no legitimate library functionality justifying the behavior.
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
Credential / info stealerFind it
Scan your lockfiles (package-lock.json, pnpm-lock.yaml, yarn.lock, requirements.txt, poetry.lock, etc.) and build artifacts for npm-sandbox-research-c5d6 (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 npm-sandbox-research-c5d6 across your stack and pipelines.
If you installed it — respond
npm-sandbox-research-c5d6 is built to steal secrets, so assume every credential the build or runtime could read is compromised. Remove it from your project and lockfile, then rotate ALL exposed secrets — npm/registry tokens, cloud keys, CI/CD secrets, SSH keys, and any .env values — from a known-clean machine. Audit logs for unauthorized use of those credentials.
Did it already run?
If npm-sandbox-research-c5d6 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 npm-sandbox-research-c5d6 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 npm-sandbox-research-c5d6-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the credential exfiltration and severs the channel.