A tool on Linux to scan for inboxes on other mailservers?
I know this is basically a spam tool.
I think to know that you can query some info from a mailserver to test if an address exists.
I would like to find hidden addresses of some companies, for example I want to test if [email protected] exists.
Anyone know how to do that?
Update
I learned quite a bit
Mailserver block the requests that are used to get a list of inboxes ("accounts")
many servers will block mailservers that are not on an allowlist
many servers will block servers, if mails were sent to nonexistent addresses a couple of times
the message "recipient not known" will not appear often, as servers may "black hole" a senders mail and cut off the connection without sending the status message back