Review your favorite Linux distribution.
Go Back > Forums > Linux Forums > Linux - Security
User Name
Linux - Security This forum is for all security related questions.
Questions, tips, system compromises, firewalls, etc. are all included here.


  Search this Thread
Old 03-30-2005, 02:35 AM   #1
Registered: Nov 2003
Location: Bristol, Britain
Distribution: Slackware
Posts: 902

Rep: Reputation: 153Reputation: 153
SMTP "open relay" and SMTP AUTH

Not a specific LINUX question but it's asking and answering may help others in the community.

Over the last few days I've been receiving a lot of bounced "spam" that appears to have been sent from my email address. With minimal of effort I sent an email from my home machine using my ISP SMTP server but with my work email address to a ficticious address. The email bounced as it couldn't find the fictious address and the next morning appeared in the inbox on my machine at work!

It therefore appears that my ISP uses an SMTP "open relay", which will allow anybody, anywhere to use their server to email whomever they want. What pressure could be brought on them so that they clean up their act?

Is there an ISP that I can use that uses a more secure SMTP?

Thanks for any advice
Old 03-30-2005, 02:43 AM   #2
Registered: Feb 2005
Location: South Africa
Distribution: SuSE
Posts: 60

Rep: Reputation: 15
To my knowledge, and I stand to be corrected, when it is noticed that they are an open relay they will be sent a mail to say close the hole or you will be blacklisted. (This happened to a clint of mine who was running an open relay.)
Old 10-09-2006, 06:45 AM   #3
Registered: Nov 2003
Location: Bristol, Britain
Distribution: Slackware
Posts: 902

Original Poster
Rep: Reputation: 153Reputation: 153
My ISP ( still seems to be operating an "Open Relay" and is not responding to my requests to stop. Is there any other organisation that I can report this to?

Old 10-11-2006, 08:19 AM   #4
Registered: Aug 2004
Location: Europe
Posts: 608

Rep: Reputation: 50
You can test whether the SMTP server really is an open relay in or


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is Off
HTML code is Off

Similar Threads
Thread Thread Starter Forum Replies Last Post
postfix and smtp auth FragInHell Linux - Software 2 10-05-2005 06:23 AM
Open relay SMTP jamesdin Debian 6 05-20-2005 10:27 AM
What's going on with this SMTP AUTH. exper Linux - Software 0 12-25-2004 02:58 AM
setting up a SMTP server with an "open" relay zyrtech Slackware 0 10-25-2003 09:13 AM
What is a good "pop before smtp relaying," Program? gsmonk Linux - Networking 2 04-09-2003 05:38 AM > Forums > Linux Forums > Linux - Security

All times are GMT -5. The time now is 03:16 AM.

Main Menu
Write for LQ is looking for people interested in writing Editorials, Articles, Reviews, and more. If you'd like to contribute content, let us know.
Main Menu
RSS1  Latest Threads
RSS1  LQ News
Twitter: @linuxquestions
Open Source Consulting | Domain Registration