checkmate-remediation-assistantnpm
Advisory published Updated
checkmate-remediation-assistant is a confirmed malicious npm package (MAL-2026-17572) 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 checkmate-remediation-assistant (npm)
What this malware does
[email protected] contains no functional code: its only behaviour is a preinstall script that runs node index.js on npm install. index.js collects the install directory, the user's home directory, hostname, username and DNS servers, and the full contents of /etc/passwd and /etc/hosts, then sends them as JSON in an HTTPS POST to 9q0lp9mr6ek7nrnklhzkmbpuglmda4yt.oastify.com, a Burp Collaborator endpoint. The npm account testneo7755 published it on 2026-10-05 and it was unpublished about two minutes later; the same account published with-cte the same day with the same index.js and a different Collaborator subdomain.
The package's package.json declares a preinstall hook that runs index.js on npm install. index.js collects os.hostname(), os.userInfo(), the home directory, DNS server configuration, __dirname, the local package.json, and the contents of /etc/passwd and /etc/hosts, then transmits the collected data over HTTPS to a hardcoded Burp Collaborator (oastify.com) subdomain (9q0lp9mr6ek7nrnklhzkmbpuglmda4yt.oastify.com). The destination is an out-of-band interaction server not associated with any declared publisher or documented package purpose, and the exfiltration fires automatically on default install without user interaction.
Malicious versions
Indicators of compromise (SHA-256)
Detection & response playbook
Credential / info stealerFind it
Search your lockfiles and build artifacts for checkmate-remediation-assistant (version 1.0.0).
If you installed it — respond
checkmate-remediation-assistant 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 checkmate-remediation-assistant was installed, its post-install payload may already have run. Removing the package does not undo that — check outbound connections and credential use from the install window onward.
Frequently asked questions
Campaign
References
Credits
- Amazon Inspector · finder
- InvisiRisk, Inc. · finder
Detect & block this
O3 blocks checkmate-remediation-assistant-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the credential exfiltration and severs the channel.