Deserialization Vulnerability in Microsoft Exchange Server by Microsoft
CVE-2026-87692

7.8HIGH

Key Information:

Vendor

Microsoft
Status
Microsoft Exchange Server 2016 Cumulative Update 23
Microsoft Exchange Server 2019 Cumulative Update 14
Microsoft Exchange Server Subscription Edition Rtm
Vendor
CVE Published:
13 October 2026

What is CVE-2026-87692?

A vulnerability in Microsoft Exchange Server allows authorized attackers to exploit deserialization of untrusted data, potentially gaining elevated privileges within the application. This can lead to unauthorized actions within the affected server, posing significant risks if not addressed. It is crucial for organizations using this software to apply the necessary patches to mitigate the threat.

Affected Version(s)

Microsoft Exchange Server 2016 Cumulative Update 23 x64-based Systems 15.01.0.0 < 15.01.2507.077

Microsoft Exchange Server 2019 Cumulative Update 14 x64-based Systems 15.02.0.0 < 15.02.1544.050

Microsoft Exchange Server Subscription Edition RTM x64-based Systems 15.02.0.0 < 15.02.2562.056

References

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

CVSS V3.1

Score:
7.8
Severity:
HIGH
Confidentiality:
High
Integrity:
High
Availability:
High
Attack Vector:
Local
Attack Complexity:
Low
Privileges Required:
Low
User Interaction:
None
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.