BleepingComputer reports that Microsoft has addressed a widespread false positive issue within Exchange Online that improperly flagged as malware and quarantined image-containing emails, including those with image signatures, within hours of being reported by several users.
"We've confirmed this issue is resolved after implementing a mitigation within the service. Telemetry shows over 99% of impacted emails have been unblocked and automatically replayed," said Microsoft, which earlier noted an issue within its malware detection systems and the adoption of a fix that facilitated the unblocking of wrongly quarantined emails. Such a fix comes after system administrators reported the issue, with one noting its impact on outbound traffic and another detailing its effect on inbound and intra-organizational communications. "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," said one of the reporting system admins on Reddit.
