CVE-2026-78450

Use after free in Reliable Multicast Transport Driver (RMCAST) allows an unauthorized attacker to execute code over a network.

CVSS v3 8.1 HIGH

8.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.2 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-78450	Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:microsoft:windows_10_1809:::::::x64:*
	cpe:2.3:o:microsoft:windows_10_1809:::::::x86:*
	cpe:2.3:o:microsoft:windows_server_2019:::::::x64:*
	cpe:2.3:o:microsoft:windows_server_2022:::::::x64:*
	cpe:2.3:o:microsoft:windows_server_2025:::::::x64:*

History

16 Sep 2026, 20:30

Type	Values Removed	Values Added
CPE		cpe:2.3:o:microsoft:windows_server_2022:::::::x64:* cpe:2.3:o:microsoft:windows_10_1809:::::::x64:* cpe:2.3:o:microsoft:windows_server_2019:::::::x64:* cpe:2.3:o:microsoft:windows_server_2025:::::::x64:* cpe:2.3:o:microsoft:windows_10_1809:::::::x86:*
References	~~() https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-78450 -~~	() https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-78450 - Vendor Advisory
First Time		Microsoft windows Server 2022 Microsoft Microsoft windows 10 1809 Microsoft windows Server 2019 Microsoft windows Server 2025

Information

Published : 2026-09-08 18:20

Updated : 2026-09-16 20:30

NVD link : CVE-2026-78450

Mitre link : CVE-2026-78450

CVE.ORG link : CVE-2026-78450

JSON object : View

Products Affected

microsoft

windows_server_2019
windows_server_2022
windows_10_1809
windows_server_2025

CWE

CWE-416

Use After Free

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