Microsoft Exchange Server Elevation of Privilege Vulnerability

What privileges could be gained by an attacker who successfully exploited the vulnerability?
An attacker could gain elevated privileges beyond those normally available to them, allowing actions such as accessing restricted information or performing operations that are typically limited to more highly privileged users or administrators.

How could an attacker exploit this vulnerability?
An attacker with a low-privilege user account and an assigned mailbox, could exploit weaknesses in how Exchange validates requests and identity tokens to impersonate another user. By doing so, the attacker could then access mailboxes through Exchange services as if they were that user.

Security updates
15.02.2562.045 — https://support.microsoft.com/help/5103212
15.02.1748.048 — https://support.microsoft.com/help/5103213
15.01.2507.071 — https://support.microsoft.com/help/5103215
15.02.1544.043 — https://support.microsoft.com/help/5103214