Internet TCP port 636 is typically used for LDAP over SSL (LDAPS). This protocol is used by directory servers such as Microsoft's Active Directory, Novell's eDirectory, and OpenLDAP among others. It provides a secure method of connecting to a directory server over the internet. The SSL layer provides encryption, which secures the data that is being exchanged between the client and the server.
TCP port 636 is typically used for LDAP over SSL (LDAPS). In the past, hackers have exploited this port by performing man-in-the-middle attacks, where they intercept and possibly alter the communication between two parties who believe they are directly communicating with each other. They can also exploit vulnerabilities in the SSL/TLS protocol itself, such as the infamous Heartbleed bug. Additionally, if a server is misconfigured to allow anonymous bind, a hacker can retrieve sensitive information. Lastly, hackers can perform a Denial of Service (DoS) attack on port 636, rendering the service unavailable to legitimate users.
