Directory & authenticationTCP 49 Encrypted
Port 49: TACACS+
TACACS+
Device administration AAA, popular for network equipment. Encrypts the entire packet body and separates authentication, authorisation and accounting.
How attackers abuse it
- Weak shared keys.
- Single server without redundancy locking administrators out.
How to defend it
- Strong keys, redundant servers, and a documented break-glass local account.
Exam tip
Choose TACACS+ for granular command authorisation on network devices.