71 lines
No EOL
2.5 KiB
Markdown
71 lines
No EOL
2.5 KiB
Markdown
● Given the exposed Docker API and high CPU usage, I strongly recommend starting with a fresh Linode. The privileged container access means attackers could have gained full system control.
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Why fresh start is safer:
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1. Persistent access: Attackers often install backdoors that survive container removal
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2. Rootkit detection: Sophisticated compromises are hard to fully detect and remove
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3. Time vs security: Rebuilding is faster than forensic analysis for production systems
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If you must keep this instance:
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1. Immediate isolation: Disconnect from network, change all credentials
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2. Full forensic analysis: Requires security expertise to ensure complete cleanup
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3. Higher risk: Potential for undetected persistence mechanisms
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For a production CI system, the clean rebuild approach is more secure and time-efficient in the long run.
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> What simple steps can I take in the future to make sure this won't happen even as I am setting up my podman containers and testing them?
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● Critical Security Steps for Future Setup:
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1. NEVER Expose Docker/Podman API Publicly
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# UNSAFE (what caused the issue):
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podman run -p 2375:2375 --privileged ...
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# SECURE Alternatives:
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# Use UNIX socket (local only)
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podman run -v /var/run/podman.sock:/var/run/podman.sock
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# Or use SSH tunnel for remote access
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ssh -L 2375:localhost:2375 user@host
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2. Firewall First Approach
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# Block all incoming by default
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sudo ufw default deny incoming
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sudo ufw default allow outgoing
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# Only open specific needed ports
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sudo ufw allow ssh
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sudo ufw allow 80,443 # web only if needed
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sudo ufw enable
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3. Avoid Privileged Containers
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# Instead of --privileged, use specific capabilities:
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podman run --cap-add NET_ADMIN --cap-add SYS_ADMIN ...
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# Or use security opts:
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podman run --security-opt=no-new-privileges ...
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4. Test in Isolated Network
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# Create internal network
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podman network create ci-network
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# Run containers on internal network only
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podman run --network ci-network ...
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● 5. Monitoring During Setup
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# Watch CPU/memory during testing
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htop
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# Monitor network connections
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sudo ss -tulpn
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# Check container processes
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podman top <container>
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6. Use Temporary Testing Environment
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- Test container configurations on local machine first
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- Use development Linode that can be easily rebuilt
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- Never expose testing containers to public internet
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The key is: never expose container management APIs (Docker/Podman ports) to the internet, and always start with a deny-all firewall policy. |