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Microsoft Exchange Server Hacks: Everything You Need to Know — Gradient Cyber

Written by Neal Hartsell | Jan 9, 2022 9:46:00 AM

The 2021 Microsoft Exchange Data Breach may go down as one of the most significant cybersecurity events of the 21st century. Since January, over 250,000 organizations across the globe have been affected, exposing millions of users to a range of cyber threats. The financial toll of this breach is expected to reach trillions, and the full ramifications will take years to fully understand.

This breach serves as a stark reminder for organizations to reassess their cybersecurity measures and ensure they are equipped to handle emerging threats. In this article, we’ll break down the key vulnerabilities exposed by the Microsoft Exchange Data Breach, how to mitigate these threats, and steps you can take to strengthen your cybersecurity.

The 2021 Microsoft Exchange Data Breach: What Happened?

On January 3, 2021, Volexity, a network security service, detected suspicious behavior on two Microsoft Exchange servers. Upon investigation, cybersecurity professionals discovered that massive amounts of data were being transmitted to unknown IP addresses. This led to the discovery of four zero-day exploits being executed against on-premise Microsoft Exchange servers.

These vulnerabilities provided attackers with access to user emails, passwords, and administrative controls. By March 2, 2021, Microsoft had acknowledged the breach and began releasing updates for affected Exchange versions (2010, 2013, 2016, and 2019). However, by March 9, more than 250,000 servers had already been compromised globally.

Who Is Behind the Attacks?

State and non-state actors quickly capitalized on the breach. Groups such as HAFNIUM, the Winniti Group, and APT27 launched sophisticated exploits against vulnerable systems. Research shows that:

  • 17% of attacks targeted U.S. organizations.
  • 6% targeted Germany.
  • 5% targeted the UK and the Netherlands.
  • 4% targeted Russian assets.

Sectors most affected include:

  • 23% of attacks targeted military and government assets.
  • 15% targeted manufacturing.
  • 14% targeted financial organizations.
  • 7% targeted software companies.
  • 6% targeted the healthcare sector.

Notable organizations like the European Banking Authority and the Norwegian Parliament have already confirmed breaches. As of March 12, 2021, around 125,000 servers remained unpatched, leaving these systems vulnerable to further exploitation.

What Organizations Are at Risk?

If your organization uses on-premise Microsoft Exchange servers, it’s critical to immediately follow Microsoft’s patching instructions for the following vulnerabilities:

  • CVE-2021-26855
  • CVE-2021-26857
  • CVE-2021-26858
  • CVE-2021-27065

Cloud-based users of Office365 are not directly affected by this breach, but organizations working with impacted partners, vendors, or clients should assess their exposure to any compromised data.

The Fallout: Ransomware and Escalating Attacks

In the aftermath of the Microsoft Exchange Data Breach, several ransomware groups have launched attacks, including DearCry, REvil, and Black Kingdom. These ransomware strains are exploiting the vulnerabilities left by the breach. For instance, REvil targeted Taiwanese tech company Acer in what is described as the largest ransomware attack to date, demanding $50 million.

What Can You Do to Protect Your Organization?

The Microsoft Exchange Data Breach highlights the importance of proactively addressing cybersecurity vulnerabilities before they escalate. Here’s what your organization can do now:

  • Patch vulnerabilities immediately according to Microsoft’s guidance.
  • Strengthen email and administrative controls to prevent unauthorized access.
  • Monitor network activity closely for signs of unusual behavior or attacks.
  • Conduct a comprehensive security audit to identify additional weak points.

Next-Generation Cybersecurity Solutions

The 2021 Microsoft Exchange Data Breach is a wake-up call for organizations worldwide. Cybercriminals are becoming increasingly emboldened, and it’s no longer a question of if your organization will face a cyberattack—it’s a matter of when.

Gradient’s next-generation cybersecurity platform offers the visibility you need to monitor network vulnerabilities and mitigate threats before they impact your business. Manage your entire cybersecurity infrastructure from a single, easy-to-use platform and protect your organization from catastrophic losses.

Ready to strengthen your cybersecurity?

Contact us today to schedule a demo and learn more about how Gradient Cyber can protect your business.