Live data from Hacker News

You don’t need a password. Posterous fail.

blog.dustincurtis.com

1–10 of 84 posts

Re: You don’t need a password. Posterous fail.

#3
It's possible to forge headers in certain circumstances. It's not easy. And this is the first time this has happened.

It's ridiculously easy to forge email headers. Headers are manually created whenever programmatically sending email messages. That's how messages can be sent from addresses that don't exist, like devnull@example.com or noreply@yourdomain.com. They don't even send a confirmation email that you have to approve before stuff is posted?

Re: You don’t need a password. Posterous fail.

#7
post #6

It is easy. $ /usr/sbin/sendmail -f dustin@dustincurtis.com dustin@posterous.com Subject: hi Spam spam spam ^D

You have to know his email address.

One quick whois lookup, and I found the email he was likely sending from. His site has another email listed, so I did a little digging.

Re: You don’t need a password. Posterous fail.

#8
post #3

It's possible to forge headers in certain circumstances. It's not easy. And this is the first time this has happened. It's ridiculously easy to forge email headers. Headers are manually created whenever programmatically sending email messages. That's how messages can be sent from addresses that don't exist, like devnull@example.com or noreply@yourdomain.com. They don't even send a confirmation email that you have to…

No, they don't.

Re: You don’t need a password. Posterous fail.

#9
post #3

It's possible to forge headers in certain circumstances. It's not easy. And this is the first time this has happened. It's ridiculously easy to forge email headers. Headers are manually created whenever programmatically sending email messages. That's how messages can be sent from addresses that don't exist, like devnull@example.com or noreply@yourdomain.com. They don't even send a confirmation email that you have to…

As I understand it, they send you a mail telling you about the post and letting you remove it. Not perfect, but probably works 99% of the time.

Re: You don’t need a password. Posterous fail.

#10
post #3

It's possible to forge headers in certain circumstances. It's not easy. And this is the first time this has happened. It's ridiculously easy to forge email headers. Headers are manually created whenever programmatically sending email messages. That's how messages can be sent from addresses that don't exist, like devnull@example.com or noreply@yourdomain.com. They don't even send a confirmation email that you have to…

Headers are manually created whenever programmatically sending email messages

To clarify this a little, in case anyone isn't familiar, to send an email message programmatically, you basically just send a string with some headers and body content to the email server. Here are what the headers look like:

  Date: Sat, 13 Jun 2009 06:53:06 -0400
  From: Mail Delivery Subsystem 
  Message-Id: 
  To: 
To change the sender, all you'd need to do is change the from line. For example:

  From: Steve Jobs 
A default sendmail implementation will deliver that message all day. Email headers should never be used for authentication.
Post reply on HN