AWS Lightsail Malware Cleanup & Hardening

My corporate site runs on an Nginx + Node.js stack inside an Amazon Lightsail instance. It has suddenly gone offline and the behavior suggests a malware compromise rather than a simple configuration error. No security measures were put in place earlier, so I need an experienced engineer to step in quickly.

After restoring access, I want the environment professionally disinfected, every backdoor closed, and the server hardened so this does not recur. Familiarity with AWS CLI, SSH hardening, malware scanners, log forensics, and typical Linux tools will be essential.

Deliverables:
• Bring the site back online with full functionality
• Remove any malicious code or files and verify integrity of the Node.js application
• Apply server-level hardening (firewall rules, service lockdowns, regular patching strategy)
• Provide a concise report detailing findings, actions taken, and recommended ongoing maintenance

Please outline your approach and estimated timeline so we can get moving right away.