Cross-Site Scripting Vulnerability in Microsoft Exchange Server
CVE-2026-55008

9.6CRITICAL

Key Information:

Vendor

Microsoft
Status
Microsoft Exchange Server 2016 Cumulative Update 23
Microsoft Exchange Server 2019 Cumulative Update 14
Microsoft Exchange Server 2019 Cumulative Update 15
Microsoft Exchange Server Subscription Edition Rtm
Vendor
CVE Published:
14 July 2026

What is CVE-2026-55008?

A cross-site scripting vulnerability exists in Microsoft Exchange Server that improperly neutralizes input during web page generation. This flaw may allow an unauthorized attacker to perform spoofing attacks, potentially compromising the integrity of the application and the server's communications over a network. To mitigate risks, it is crucial for affected users to apply the latest updates and patches provided by Microsoft.

Affected Version(s)

Microsoft Exchange Server 2016 Cumulative Update 23 x64-based Systems 15.01.0.0 < 15.01.2507.071

Microsoft Exchange Server 2019 Cumulative Update 14 x64-based Systems 15.02.0.0 < 15.02.1544.043

Microsoft Exchange Server 2019 Cumulative Update 15 x64-based Systems 15.02.0.0 < 15.02.1748.048

References

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

CVSS V3.1

Score:
9.6
Severity:
CRITICAL
Confidentiality:
High
Integrity:
High
Availability:
High
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
None
User Interaction:
Required
Scope:
Changed

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.