CVE-2026-78450 - Vulnerability Details - OpenCVE

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

No CVSS v4.0

Attack Vector Network

Attack Complexity High

Privileges Required None

Scope Unchanged

Confidentiality Impact High

Integrity Impact High

Availability Impact High

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

No EPSS score available.

Key SSVC decision points have not yet been added.

Vendors	Products
Microsoft Subscribe	Windows 10 1809 Subscribe Windows Server 2019 Subscribe Windows Server 2022 Subscribe Windows Server 2025 Subscribe

No data.

No data.

No data.

Advisories

No advisories yet.

Fixes

Solution

No solution given by the vendor.

Workaround

No workaround given by the vendor.

References

Link	Providers
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-78450

History

Tue, 08 Sep 2026 17:30:00 +0000

Type	Values Removed	Values Added
Description		Use after free in Reliable Multicast Transport Driver (RMCAST) allows an unauthorized attacker to execute code over a network.
Title		Windows Reliable Multicast Transport Driver (RMCAST) Remote Code Execution Vulnerability
First Time appeared		Microsoft Microsoft windows 10 1809 Microsoft windows Server 2019 Microsoft windows Server 2022 Microsoft windows Server 2025
Weaknesses		CWE-416
CPEs		cpe:2.3:o:microsoft:windows_10_1809:::::::x86:* cpe:2.3:o:microsoft:windows_server_2019:::::::: cpe:2.3:o:microsoft:windows_server_2022:::::::: cpe:2.3:o:microsoft:windows_server_2025::::::::
Vendors & Products		Microsoft Microsoft windows 10 1809 Microsoft windows Server 2019 Microsoft windows Server 2022 Microsoft windows Server 2025
References		https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-78450
Metrics		cvssV3_1 `{'score': 8.1, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C'}`

Projects

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MITRE

Status: PUBLISHED

Assigner: microsoft

Published: 2026-09-08T17:18:23.871Z

Updated: 2026-09-08T18:38:34.250Z

Reserved: 2026-08-24T16:21:50.286Z

Link: CVE-2026-78450

Vulnrichment

No data.

NVD

Status : Awaiting Analysis

Published: 2026-09-08T18:20:43.340

Modified: 2026-09-08T18:38:46.007

Link: CVE-2026-78450

Redhat

No data.

OpenCVE Enrichment

No data.

Weaknesses

CWE-416

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