Should port 27017 ever be open to the internet?

Never. Exposing port 27017 directly to the public web exposes your database to automated ransomware bots. Connect exclusively via private subnets or SSH tunnels.

How do I secure MongoDB port 27017?

Enable 'security.authorization: enabled' in mongod.conf, create strong administrative and user accounts, and bind only to internal IP addresses.

How do I verify if port 27017 is publicly exposed?

Check your server IP in our Open Port Checker tool. If port 27017 is open, block it immediately in your firewall rules.

Home/Open Port Checker/Port 27017

Port 9200 Port 51820

Registered Port Reference

Port 27017: MongoDB Database (TCP)

Default listening port for MongoDB NoSQL document database instances.

Port Number

27017

Transport

TCP

Security Risk

Critical

Standard / RFC

MongoDB Wire

Test Port 27017 Reachability Live

Verify whether Port 27017 is open, closed, or filtered on your server or public IP address.

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Service Architecture & Function

Port 27017 is the default port for MongoDB standalone daemons, replica sets, and mongos query routers. Drivers in Node.js, Python, and other programming languages connect to port 27017 to read and write BSON documents.

Security Profile & Hardening

Historically, default MongoDB configurations lacked authentication, leading to automated ransomware campaigns that wiped databases and demanded ransom. Always enable authorization in mongod.conf and restrict network binding to private interfaces.

Example Firewall Commands:

# UFW (Ubuntu/Debian)

sudo ufw deny 27017/tcp

# iptables (Direct Kernel)

iptables -A INPUT -p tcp --dport 27017 -j DROP