It was disclosed by Hewlett Packard Enterprise (HPE) that the suspected Russian hackers known as Midnight Blizzard were found to have infiltrated the company’s Microsoft Office 365 email environment to steal data and exfiltrate a small percentage of mailboxes belonging to individuals from their cybersecurity team and other departments. In the new SEC filing, the company stated that they were made aware on December 12th, 2023, that threat actors had gained access to their cloud-based email environment and had been exfiltrating data beginning in May 2023. HPE attributed the attack to the nation-state actor based upon their investigation. The threat actor, Midnight Blizzard (also known as APT29, CozyBear, and BlueBravo), is the same threat actor Microsoft identified as being behind the breach of their own corporate systems in late November 2023, targeting the email accounts of senior executives and other individuals from their cybersecurity and legal departments. Microsoft’s recently reported that the security incident came just days before HPE’s disclosure, but it’s not yet known if the two (2) incidents are related. While the investigation of HPE’s current breach is still ongoing, the company did suggest that they believe it is related to a previous breach that occurred in May 2023, also attributed to Midnight Blizzard, where the threat actor obtained unauthorized access to their SharePoint files and exfiltrated a limited number of them. While the threat actors persisted in the network undetected for up to six (6) months, there have been no details around the scale of the attack, or the exact nature of the emails accessed. HPE determined that there has not yet been any operational impact nor is it likely to cause any material financial impact to the company.