37. Enumeration: NetBIOS, SMB, SNMP, LDAP, SMTP, NFS and DNS
37.3 SNMP Enumeration
SNMP (Simple Network Management Protocol) – devices (routers, printers, servers) monitoring sathi. UDP 161. Junya setups madhe community string public (read) / private (read-write) – passwords sarkhe, pan plain/default!
sudo apt install -y snmp snmp-mibs-downloader snmpcheck
# Walk the tree with community "public" (lab only – Metasploitable may expose SNMP)
snmpwalk -v2c -c public 192.168.56.20
snmp-check 192.168.56.20 -c public
Jar SNMP open asel tar hostname, interfaces, processes, sometimes software inventory – attacker la map milto. Write community asel tar config pan badlu shakto – khup dangerous.
Defence: default communities kadhun taka; SNMPv3 (auth + encryption) prefer kara; ACL – fakt NMS IP allow; UDP 161 internet kade expose karu naka; read-only wherever possible. He khup important aahe.
Ravindra Bagale's Tip
Students public community lab madhe shikun real router var try kartat "baghto". He unauthorized access aahe. SNMP enum fakt tumcha lab device kiwa written scope. Interview: "How do you harden SNMP?" – v3, ACL, no defaults.
Lab
nmap -sU -p 161 192.168.56.20 – SNMP open aahe ka? Open asel tar snmpwalk -v2c -c public 192.168.56.20 try kara (lab). Closed asel tar note: "service not exposed – good for this host" ani SNMPv3 defence 5 bullets aaplya notes madhe liha.