Weak Authentication in Microsoft Exchange Server Exposes Network Elevation Vulnerability
CVE-2026-118157

7.2HIGH

Key Information:

Vendor

Microsoft
Status
Microsoft Exchange Server Subscription Edition Rtm
Vendor
CVE Published:
10 November 2026

What is CVE-2026-118157?

A security flaw in Microsoft Exchange Server allows attackers with existing access to exploit weak authentication mechanisms, potentially enabling them to elevate their privileges within the network. This could allow unauthorized actions or access to sensitive data within the server environment, highlighting the importance of robust authentication and regular security updates.

Affected Version(s)

Microsoft Exchange Server Subscription Edition RTM x64-based Systems 15.02.0.0 < 15.02.2562.057

References

https://msrc.microsoft.com/update-guide/vulnerability/CVE...
vendor-advisorypatch

CVSS V3.1

Score:
7.2
Severity:
HIGH
Confidentiality:
High
Integrity:
High
Availability:
High
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
High
User Interaction:
None
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.