We've always gotten a lot of phishing attacks since we started on Sophos Email Protection. Maybe slightly less than when we just had the standard MS365 spam protection. I collect many of the blatant ones that get through, which is at least once a day. And our users use the Report Message button to report to Sophos. To implement Sophos we are supposed to have a rule in place to pass all mail (Sophos doc refers to it as "clean" mail) from Sophos to the user.
The last few weeks we have been getting alerts from MS 365: "Informational-severity alert: Phish delivered due to an ETR override". This is alerting us to the fact that the Sophos EOP override rule has forced MS 365 to pass along a phishing email to us. So with each phishing email, I get to go through a bunch of emails:
--2 or 3 people asking me if the message is OK
--1-3 people reporting via Sophos
-- And now, multiple alerts from MS telling me their basic email protection service can see it's a phish but the advanced Sophos tool can't--an alert for each user that gets the phish, which usually is several.
I don't want to turn off alerts from MS, but I also don't need alerts from MS telling me what I know (that a phishing email was let through by Sophos).
Anyone know why this started in last few weeks? Anyone know how to turn it off for just one ETR rule?
Sr. Director, IT, NDIA
Here is the response from Sophos Support Team.
The samples submitted are a part of new zero-day campaign and we have update our detection level to block them. This will help block the similar type of samples…
Thank you for contacting the Sophos Community.
I would recommend you to get a case open with support, and submit the email samples directly to the engineer, so they can pass them down directly to our Labs Team.
Checking internally I noticed an open case for the same, on Sep 1 after the samples were submitted to Labs, they mentioned they aren’t Phish but rather Spam.
Thanks! No, these are Phishes. And now it's suddenly gotten worse--when users see the phish and report it, MS is reporting the copies of the emails sent to me as ETR Overrides!
Thank you for the follow-up.
In that case, I would recommend you to open a case with support to get this investigated, feel free to share the Case ID with me once you have it.
Case 04386649 ... I uploaded 30 of hundreds of examples.
Thank you for the Case ID.
I can see one Engineer has already started to analyze the sample provided.
I have left a note on the case as well for the engineer to check.