Connect#

openssl

openssl s_client -connect $target:pop3s

curl

curl -k "pop3://$target" --user user:p4ssw0rd -v

Login, read, send, everything#

Just… use a GUI app. Thunderbird especially sucks at trusting self signed certs, hence evolution

sudo apt install evolution

POP3 commands#

+OK POP3
USER marlin@inlanefreight.htb
+OK Send your password
PASS poohbear
+OK Mailbox locked and ready
LIST
+OK 1 messages (601 octets)
1 601
.
RETR 1