Russia-linked Midnight Blizzard stole email of more Microsoft customers

Russia-linked Midnight Blizzard stole email of more Microsoft customers

Microsoft warned more customers about email theft linked to the previously reported Midnight Blizzard hacking campaign.

The Russia-linked cyberespionage group Midnight Blizzard continues to target Microsoft users to steal other emails, warn the IT giant.

The company is identifying more customers targeted by the Midnight Blizzard hacking campaign following Microsoft’s corporate infrastructure breach.

In January, Microsoft warned that some of its corporate email accounts were compromised by a Russia-linked cyberespionage group known as Midnight Blizzard. The company notified law enforcement and relevant regulatory authorities.

Microsoft also announced that the Russia-linked APT Midnight Blizzard that hit the company in late November 2023 has been targeting organizations worldwide as part of a large-scale cyberespionage campaign.

Now Microsoft’s incident response team is contacting customer administrators to provide a secure portal that allows them to view emails stolen by the Russia-linked Midnight Blizzard APT group.

You are receiving this notification because emails were exchanged between Microsoft and accounts in your organization, and those emails were accessed by the threat actor Midnight Blizzard as part of their cyber-attack on Microsoft.

As part of our commitment to transparency, we are proactively sharing these emails. We have custom built a secure system to enable the approved members of your organization to review the exfiltrated emails between Microsoft and your company.  

In order to grant access to the above-referenced emails, you are required to identify authorized individuals within your organization who can nominate reviewers. As needed, please reach out to the appropriate parties in your organization who have the authority to nominate reviewers to view these emails.

At the bottom of this email is a link which will take you to a secure form where you will be asked to provide the following information:

     • Your organization’s TenantID
              o If you do not know or are unsure of your TenantID, please follow the steps outlined here: https://aka.ms/gettenantid
     • The access code located at the bottom of this email
     • The email addresses for individuals within your organization who can nominate reviewers who will be granted access to the set of exfiltrated emails.

Once you complete this form, Microsoft will contact those who have been identified with instructions on how to identify reviewers. 

Should you or your organization require support during this process please work with your Customer Success Account Manager (CSAM) or account representative(s) to open a support case and reference Microsoft Email Data Sharing.  Microsoft continues to prioritize transparency and learnings from events like these to help protect customers and our own enterprise.

Our investigation is ongoing, if we discover new information, we will tell you as soon as practicable."

This week TeamViewer discovered that a threat actor has breached its corporate network and some reports attribute the intrusion to the Russia-linked APT group APT29 (aka SVR group, BlueBravo, Cozy Bear, Nobelium, Midnight Blizzard, and The Dukes).

The unauthorized access to the IT infrastructure of the company occurred on June 26, threat actors used the credentials of a standard employee account within its IT environment.

Pierluigi Paganini

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(SecurityAffairs – hacking, newsletter)