On 2026-03-10 16:00, Ron via Talk wrote:
Anyone running Postfix to self-host email and notice that their home IP address is leaked in the first "Received: from" header? Postfix is a Mail Transfer Agent. By rights it always needs to include where the message came from. If you inject the message directly into the postfix delivery queue without coming through the SMTP/SUBMISSION interfaces then you should have no first received-from header.
That is kind of what gmail is doing. If you send a message through google from Thunderbird (in my case) they include the source address of my firewall. As for security. That is a double edged sword. Including the address of the source workstation can be important if you need to find out who physically sent the email. Lets say I use your email account to send out company secrets from my workstation. Without that first IP address it would end up with the wrong person being accused. In general knowing an un-routable 10. network address will not provide much information to a hacker unless they can get inside your network. [snip] -- Alvin Starr || land: (647)478-6285 Netvel Inc. || home: (905)513-7688 alvin@netvel.net ||