enumeration

Command	Description
A1 LOGIN username password	User's login.
1 LIST "" *	Lists all directories.
1 CREATE "INBOX"	Creates a mailbox with a specified name.
1 DELETE "INBOX"	Deletes a mailbox.
1 LSUB "" *	Returns a subset of names from the set of names that the User has declared as being active or subscribed.
1 SELECT INBOX	Selects a mailbox so that messages in the mailbox can be accessed.
1 UNSELECT INBOX	Exits the selected mailbox.
1 CLOSE	Removes all messages with the Deleted flag set.
1 LOGOUT	Closes the connection with the IMAP server.
1 FETCH 1:* (FLAGS BODY[HEADER.FIELDS (SUBJECT FROM DATE)])	Show all mails

Connect with service

telnet "$target" <port>

curl -k "imap://$ip" --user user:password -v

Get all mail

curl -k "imap://$ip/INBOX?ALL" --user user:password -v

openssl s_client -connect "$ip":imaps

Telnet smtp commands https://www.samlogic.net/articles/smtp-commands-reference-auth.htm