Microsoft is investigating an Trade On-line false constructive subject inflicting emails containing photos to be wrongly tagged as malicious and despatched to quarantine.
“Users’ email messages containing images may be incorrectly flagged as malware and quarantined,” Microsoft mentioned in a service alert posted on the Microsoft 365 admin heart two hours in the past.
“We’re reviewing service monitoring telemetry to isolate the root cause and develop a remediation plan.”
Tracked underneath EX873252, this ongoing service degradation subject appears to be widespread, in accordance with reviews from system directors, and it additionally impacts messages with picture signatures.
“Seems to only be affecting our outbound traffic and specifically for replies and forwards of previously external emails,” one admin mentioned.
“For us, it was both inbound and intra-org. Inbound only would have been much easier for me to deal with. They also basically tagged our intra as inbound from what I saw in tbr message header,” one other one added.
Redmond has but to disclose what areas are impacted by this subject and supply mitigation recommendation for impacted clients till the false constructive issues are resolved.
In October 2023, Microsoft addressed an identical subject brought on by a nasty anti-spam rule that flooded Microsoft 365 admins’ inboxes with blind carbon copies (BCC) of outbound emails mistakenly flagged as spam.
Replace August 26, 13:00 EDT: Microsoft has taken measures to maneuver professional emails mistakenly tagged as malicious out from quarantine.
“We identified an issue affecting our malware detection systems. We’ve implemented a mitigation to unblock legitimate emails that were mistakenly quarantined. The replay of impacted emails is in progress,” Microsoft mentioned.