Russian hackers stole Microsoft corporate emails in month-long breach

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Microsoft has disclosed that several of its corporate email accounts were breached by a Russian state-sponsored hacking group Midnight Blizzard. The company detected the attack on January 12, 2024. Microsoft’s internal investigation concluded that the attack was conducted by a group of Russian threat actors associated with Nobelium/APT29 (sometimes known as Midnight Blizzard or Cozy Bear). The software titan said that the threat actors breached their systems in November 2023 by conducting a password spray attack to access a legacy non-production test tenant account. Microsoft says the hackers accessed a “small percentage” of Microsoft’s corporate email accounts for over a month including accounts tied to the company’s leadership team and employees in the cybersecurity and legal departments. The company speculates that the threat actors were looking for information about their own gang.

The fact that the hackers were able to gain access to the account using a brute force attack indicates it was not protected with two-factor authentication (2FA) or multi-factor authentication (MFA), a security practice that Microsoft recommends on all types of online accounts.

How It Could Affect Your Business: Even the biggest companies can be brought low by a simple cybersecurity problem.

PDX IT to the Rescue: An endpoint detection and response solution can help businesses stop the spread of a cyberattack fast.

https://www.bleepingcomputer.com/news/security/russian-hackers-stole-microsoft-corporate-emails-in-month-long-breach/#google_vignette

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Steve Shaff, owner of PDX Information Technology Services

About the author: Steve Shaff

Steve Shaff is the owner of PDX Information Technology Services, a managed IT provider he founded in 2020. From the Tualatin office he helps businesses across Portland Metro & Southwest Washington with IT support, cybersecurity and compliance. More about Steve · Contact PDX IT

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