Authorization bypass through user-controlled key in Microsoft Exchange Server Subscription Edition RTM - CVE-2026-118150
Published: November 11, 2026
Vulnerability identifier: #VU165048
CSH Severity: Medium
CVSS v4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-118150
CWE-ID: CWE-639
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote user to escalate privileges in Microsoft Exchange Server.
The vulnerability exists due to authorization bypass through a user-controlled key in Microsoft Exchange Server when handling network requests. A remote user can manipulate a key used in authorization decisions to bypass access restrictions and escalate privileges.
Affected software
Microsoft Exchange Server Subscription Edition RTM
How to mitigate CVE-2026-118150
Install security update from vendor's website.
Microsoft Exchange Server Subscription Edition RTM - update to 15.02.2562.057