cancel
Showing results for 
Search instead for 
Did you mean: 
cancel
572
Views
0
Helpful
2
Replies

ASA regex to filter smtp traffic

gregbeifuss
Level 1
Level 1

I'd like to put a rule in place on our ASA that will drop any incoming SMTP traffic that has a FROM address matching our domain. For example, drop any inbound SMTP traffic that has a from address of *@mycompany.com. However, I'm really unsure how to do this. Are there any articles or an overview that someone can point me to?

I'm interested in doing this as I believe it will help drop spoofed email traffic at the edge, before it even hits our antispam device.

Thanks,

Greg

2 Replies 2

Collin Clark
VIP Alumni
VIP Alumni

Greg,

Check this link. It prevents your email server from being a relay which I think is what your after.

https://packetpros.com/cisco_kb/ASA_Prevent_MailRelay.html

Hope it helps.

Hi Collin,

I'm looking more to prevent spam messages getting to my users where the message takes the format FROM Greg@company.com TO greg@company.com as we should not be receiving messages like this inbound. Relaying is already disabled on my mailserver.

Greg

Getting Started

Find answers to your questions by entering keywords or phrases in the Search bar above. New here? Use these resources to familiarize yourself with the community: