Cisco ESA append subject for Mail with no subject Header

[junajunction]

HI Guys, we have the ESA configured to append the Subject header to add Ëxternal"word or tag for every incoming mail. This is working successfully. recently an issue occured where one of the mails was not tagged with the keyword and was allowed to deliver to the mailbox. While checking the mail did not have anything given in the subject field or Subject filed was blank. 

While testing again to replicate the issue we observed that the mail is appending all other mails including the ones with blank subject from almost all other domains except the domain icloud.com. Any mail that is sent from the icloud.com domain does not get appended to the keyword and is delivered to the mailbox. 

is there any way or has anyone observed similar behaviour with the icloud domain.

Appreciate your support,

Thanks Arjun

[dmccabej]

Hello,

It sounds like the icloud emails are skipping your content filter and/or not hitting it somehow. Maybe you have another filter above with the skip-filters action that the icloud emails are hitting? Or, maybe they're hitting another mail policy where the filter is not configured?

Typically I would recommend to add a log-entry to every filter since it has no impact other than providing additional debugging information. 

It would be a bit hard to say via the forum since ideally we would need to review your configuration.

Thanks!

-Dennis M.