Remote Code Execution Vulnerability in Microsoft Exchange Server
CVE-2026-55007

8.1HIGH

Key Information:

Vendor

Microsoft
Status
Microsoft Exchange Server 2019 Cumulative Update 14
Microsoft Exchange Server 2019 Cumulative Update 15
Microsoft Exchange Server Subscription Edition Rtm
Vendor
CVE Published:
8 September 2026

What is CVE-2026-55007?

A security flaw in Microsoft Exchange Server involves a double free vulnerability, allowing unauthorized attackers to execute arbitrary code over the network. This issue can lead to significant security breaches if exploited. Users are urged to apply the latest patches to ensure their systems remain secure. For detailed guidance and updates on mitigation, refer to the official Microsoft advisory.

Affected Version(s)

Microsoft Exchange Server 2019 Cumulative Update 14 x64-based Systems 15.02.0.0 < 15.02.1544.046

Microsoft Exchange Server 2019 Cumulative Update 15 x64-based Systems 15.02.0.0 < 15.02.1748.051

Microsoft Exchange Server Subscription Edition RTM x64-based Systems 15.02.0.0 < 15.02.2562.049

References

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

CVSS V3.1

Score:
8.1
Severity:
HIGH
Confidentiality:
High
Integrity:
High
Availability:
High
Attack Vector:
Network
Attack Complexity:
High
Privileges Required:
None
User Interaction:
None
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.