CVE-2026-78450: Windows Reliable Multicast Transport Driver (RMCAST) Remote Code Execution Vulnerability
Use after free in Reliable Multicast Transport Driver (RMCAST) allows an unauthorized attacker to execute code over a network.
Other sources
Windows Reliable Multicast Transport Driver (RMCAST) Remote Code Execution Vulnerability
— Microsoft
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 10.0.20348.5622Patch KB5122882 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 10.0.17763.9245Patch KB5122876 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 10.0.26100.33438Patch KB5122871
Event History
Frequently Asked Questions
Which systems are identified as affected?
The affected software listed is Microsoft Windows 10 and Microsoft Windows Server 2019, Windows Server 2022, and Windows Server 2025.
Does exploitation require authentication or user interaction?
No. The supplied vector indicates network-based exploitation with no privileges required and no user interaction required.
What conditions make exploitation more difficult?
The attack complexity is rated high, indicating that successful exploitation requires conditions beyond simply reaching the vulnerable service over the network.
What is the potential impact of successful exploitation?
Successful exploitation can allow remote code execution and is rated as having high impact to confidentiality, integrity, and availability.