On August 6, 2025, Microsoft issued an advisory for a high-severity vulnerability affecting Microsoft Exchange hybrid environments. The vulnerability, tracked as CVE-2025-53786, allows an attacker with administrative access to an on-premises Exchange Server. This access enables privilege escalation into the connected Exchange Online environment. The vulnerability can impact the confidentiality, integrity, and availability of affected systems.

On August 6, 2025, Microsoft issued an advisory for a high-severity vulnerability affecting Microsoft Exchange hybrid environments. The vulnerability, tracked as CVE-2025-53786, allows an attacker with administrative access to an on-premises Exchange Server.
This access enables privilege escalation into the connected Exchange Online environment. The vulnerability can impact the confidentiality, integrity, and availability of affected systems.