Catch-All Email
A catch-all email address is a mailbox configured to receive messages sent to any address at a domain that does not match an existing mailbox, rather than bouncing them. For example, if only [email protected] exists, a catch-all would also deliver [email protected] or [email protected]. While convenient for capturing misaddressed mail, catch-all configurations are heavily targeted by spammers who send bulk mail to random addresses at a domain and rely on the catch-all to deliver it. Most [[email-hosting|email hosting]] providers offer catch-all as an optional setting, distinct from [[email-alias|email aliases]].
Example
A small business with catch-all enabled receives mail sent to support@, billing@, and sales@ even though only hello@ is formally configured — useful during onboarding, but increases spam exposure significantly.