A content regex rule condition "for any part of the message" containing either the '/' or '\' character (such as a URL) will always fail to match the message data.
SMG 10.7.x 10.8.0
The '/' character is a meta-character in the Messaging Gateway regular expression and in some cases is not properly escaped resulting in a failure to match the expected message data.
This issue has been addressed in SMG 10.8.1
With the 10.8.1 release, content rules containing unescaped '/' or '\' characters will match message data as expected. Additionally, existing content filtering rules which contain properly escaped '/' or '\' characters will continue to work as expected without change.
This change applies to all regular expression conditions and is not limited to the "for any part of the message" condition which failed to match in SMG 10.8.0 and earlier.