Missing authorization in Microsoft Exchange Server allows an authorized attacker to elevate privileges over a network.
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. What privileges could be gained by an attacker who successfully exploited the vulnerability? The attacker would be able to take over the mailboxes of all Exchange users, attackers can send emails, read emails, download attachments.
<a href="https://smlijun.github.io/">DongJun Kim (smlijun)</a> with UIUC, <a href="https://hwiwonl.ee/">Hwiwon Lee (hwiwonl)</a> with UIUC, <a href="https://nevul37.github.io/">Jongseong Kim (nevul37)</a> with UIUC, Younggi Park (grill66) with UIUC, <a href="https://www.linkedin.com/in/navaponpremkasem/">71C4</a>