Network, database and SSL/TLS

Network configuration

A very important thing to check when deploying an on-premise type of architecture is the networking configuration. Ensure that the Tomcat server is NOT directly accessible outside the server:

  • Close the Tomcat port (8080) on external IPs (must work on localhost)
  • Do not map the standard HTTP port (80) to the Tomcat one (8080)

When it’s possible, use a secure channel: POP3S instead POP3 (or POP3 over TLS).


You must apply your database engine security best practices.

SSL/TLS Configuration

To check the certificate, you can use openssl. To check active ciphers, you can use nmap:

# usage: [port]
echo |\
openssl s_client -connect ${REMHOST}:${REMPORT} -servername ${REMHOST} 2>&1 |\
openssl x509 -noout -subject -dates
nmap --script ssl-enum-ciphers -p ${REMPORT} ${REMHOST}

You can also use an sslyze python script which does both.

python --sslv2 --sslv3 --tlsv1 --reneg --resum --certinfo=basic --hide_rejected_ciphers --sni=SNI

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