CVE-2026-69789: Windows Reliable Multicast Transport Driver (RMCAST) Remote Code Execution Vulnerability
Heap-based buffer overflow in Reliable Multicast Transport Driver (RMCAST) allows an unauthorized attacker to execute code over an adjacent 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
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Fixed in 10.0.14393.9512Patch KB5123099 - Upgrade
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Fixed in 6.3.9600.23398Patch KB5123066 - Upgrade
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Fixed in 6.2.9200.26349Patch KB5123065 - Upgrade
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Fixed in 10.0.26100.9445Patch KB5124008 - Upgrade
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Fixed in 10.0.28000.2954Patch KB5124012 - Upgrade
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Fixed in 10.0.22631.7582Patch KB5122880 - Upgrade
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Fixed in 10.0.26100.33438Patch KB5122871 - Upgrade
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Fixed in 10.0.26200.9445Patch KB5124008 - Upgrade
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Fixed in 10.0.17763.9245Patch KB5122876 - Upgrade
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Fixed in 10.0.19045.7725Patch KB5122878 - Upgrade
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Fixed in 10.0.19044.7725Patch KB5122878 - Upgrade
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Fixed in 10.0.20348.5622Patch KB5122882
Event History
Frequently Asked Questions
What level of access does an attacker need?
The attacker does not need prior privileges or user interaction. Exploitation is assessed as requiring access from an adjacent network and having high attack complexity.
Which Windows platforms are listed as affected?
The listed platforms are Microsoft Windows 10, Windows 11, Windows Server 2012, Windows Server 2012 R2, Windows Server 2016, Windows Server 2019, Windows Server 2022, and Windows Server 2025.
What could a successful exploit allow?
A successful exploit could allow code execution and is rated as having high potential impact to confidentiality, integrity, and availability.