I recently had a spammer get a hold of one of my email account passwords and send a boatload of spam through my system before we caught them. As part of the triage, my hosting company is recommending I completely block / close port 25 and only use port 587.
My understanding was that port 25 was for non-SSL incoming SMTP and that port 587 was for SSL incoming SMTP and that it was good to have both as an option.
Thoughts? Would I run into trouble if I completely closed off 25 and only had 587 open? I did try to search for an answer on this but wasn't able to find something on this particular question. Maybe I didn't use the right phrase.
Blocking Port 25 / Only Using Port 587?
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- Site Admin
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Re: Blocking Port 25 / Only Using Port 587?
Hi,
If you block port 25 inbound you will not be able to receive emails from remote mail servers as all mail server send/receive over port 25. Please review the following article which explains the best practices for securing the MailEnable services:
https://www.mailenable.com/kb/content/article.asp?ID=ME020727
If you block port 25 inbound you will not be able to receive emails from remote mail servers as all mail server send/receive over port 25. Please review the following article which explains the best practices for securing the MailEnable services:
https://www.mailenable.com/kb/content/article.asp?ID=ME020727
Regards,
Ian Margarone
MailEnable Support
Ian Margarone
MailEnable Support
Re: Blocking Port 25 / Only Using Port 587?
But, what if I want to block port 25 from outgoing mail? Lots of attempts here to try to send email via port 25 from spoofed users. All my users are set to send via SSL port 465. I do not want any one to send mail via port 25.
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- Site Admin
- Posts: 1127
- Joined: Mon Jun 10, 2002 6:31 pm
- Location: Melbourne, Victoria, Australia
Re: Blocking Port 25 / Only Using Port 587?
Hi,
You can do this under the port settings for the SMTP Inbound. Change the drop down for port 25 to be "Never allow authentication". Then only emails for local addresses will be accepted through that port unless you have allowed them to relay via IP address.
You can do this under the port settings for the SMTP Inbound. Change the drop down for port 25 to be "Never allow authentication". Then only emails for local addresses will be accepted through that port unless you have allowed them to relay via IP address.
Re: Blocking Port 25 / Only Using Port 587?
Yes, I saw that when poking around. Thanks