Nmap is not just for port scanning. With the right flags, it reveals how a system negotiates encrypted connections, what ciphers it trusts, and whether its certificates are strong or expired. For modern infrastructure, checking TLS configuration is not optional. Weak ciphers, outdated protocols, and misconfigured certificates can open critical vulnerabilities.
The key is leveraging Nmap’s ssl-enum-ciphers and --script ssl-cert features. ssl-enum-ciphers runs a methodical sweep through available TLS protocols and ciphers, listing their strength and status. It flags insecure suites like RC4 or SSLv3, helping you enforce TLS 1.2+ or TLS 1.3 across your environment. ssl-cert inspects certificates, pulling details like issuer, expiration dates, and Subject Alternative Names, so you can spot outdated or mismatched certs before they break production.
A focused TLS scan looks like this: