Emails from outside that appear to come from the inside?

[gopunk]

does anybody know how this is done? what i'm talking about is when you receive an email with an email address in the From: field that is an address on your network, but you know that address doesn't exist, or the message didn't come from that address.

i know you can just change what the From: field says in the message you send, but isn't there some other way, such that if you send it to a bunch of different people on different netwokrs, it'll always look like your email address is on theirs? i seem to recall there was... maybe something to do with whatever mail program the server you're on is using... like sendmail or something...?

only reason i'm asking is because i have a spam filter that works well, but i'm paranoid that i'll miss an important email, so i exempt any emails coming from *edu addresses. so every once in a while, i'll get an email from Electronics@cs.washington.edu, or something like that, even though it isn't actually from a cs.washington.edu account.

 

[Lithium381]

isn't it a script that simply lies to the server and what the FROM field is?

 

[Soybomb]

You just change the from address.......you're lying to the mailserver and it doesn't know or care.

you can have your mta rewrite the address of all messages sent through it too, say for a mailing list, but the spammers are just using spamming software to do it.

 

[FoBoT]

what is the question?

you want to know how to spoof email addresses?

i am not clear what you want to know

 

[gopunk]

ah sorry i guess i wasn't clear.... i guess what i'm asking is, is is possible to write your email in a way that tells the recipient's email server to use it's own domain as the from field's domain? it occurred to me that the spammers might just be putting cs.washington.edu to the end of their from field, but that seemed unlikely to me, because it's not an immensely popular domain or anything...