SB2025080631 - Privilege escalation in Microsoft Exchange Server Hybrid Deployment
Published: August 6, 2025
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 security vulnerability.
1) Improper authentication (CVE-ID: CVE-2025-53786)
The vulnerability allows a remote attacker to escalate privileges in hybrid deployments.
The vulnerability exists due to improper authentication. A remote user with privileged access to an on-premises Exchange server can escalate privileges within the organization’s connected cloud environment without leaving easily detectable and auditable trace.
Remediation
Install update from vendor's website.