Recomendation on adding trusted domain

[Shusovit Dutta]

There is a requirement to add 5000+ trusted domains in the system, so that inbound emails can be processed. But I feel this should not be done due to risks like performance degradation, Security Vulnerabilities, spam emails etc. What else can be the risks that makes this requirement a not recommended one. 

[Vasantharajan N]

@Shusovit Dutta - Why don't you use the "Email Address filter" to accept and process the emails only from the trusted domains. 

[Shusovit Dutta]

This is for outbound emails. I want to configure it for inbound emails

[Vasantharajan N]

@Shusovit Dutta - You need to use the "Email address filters" along with "System address filter" where you control the inbound / outbound behavior

You may go through the docs site for more details and to try. 

https://www.servicenow.com/docs/r/platform-administration/system-address-filters.html

Refer the KB "How to use email address filters to ignore any email from any sender?" that helps you

https://support.servicenow.com/kb?id=kb_article_view&sysparm_article=KB0869547

[Vishal Jaswal]

@Shusovit Dutta My recommendation is to raise HI Ticket and talk to ServiceNow Support or ask them to get this answer from their engineering team. The closest functionality is only to track such via Instance Security Center rather than actually ensuring only trusted domains e-mail can be considered as processed in sys_email table.