CVE-2026-54982: Windows Reliable Multicast Transport Driver (RMCAST) Remote Code Execution Vulnerability

Published Jul 14, 2026
·
Updated

Integer underflow (wrap or wraparound) 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

50 affected componentsFixes available
Microsoft Windows Reliable Multicast Transport Driver (RMCAST)
Microsoft Windows Server 2012<6.2.9200.26226
6.2.9200.26226
Microsoft Windows Server 2012 R2<6.3.9600.23291
6.3.9600.23291
Microsoft Windows Server 2012 R2<6.3.9600.23291
6.3.9600.23291
Microsoft Windows 11=26H1
10.0.28000.2525
Microsoft Windows Server 2016<10.0.14393.9339
10.0.14393.9339
Microsoft Windows Server 2016<10.0.14393.9339
10.0.14393.9339
Microsoft Windows 10=1607
10.0.14393.9339
Microsoft Windows Server 2025<10.0.26100.33158
10.0.26100.33158
Microsoft Windows Server 2012<6.2.9200.26226
6.2.9200.26226
Microsoft Windows 10=1607
10.0.14393.9339
Microsoft Windows 11=24H2
10.0.26100.8875
Microsoft Windows 11=26H1
10.0.28000.2525
Microsoft Windows 11=25H2
10.0.26200.8875
Microsoft Windows 11=25H2
10.0.26200.8875
Microsoft Windows 10=22H2
10.0.19045.7548
Microsoft Windows 10=22H2
10.0.19045.7548
Microsoft Windows Server 2025<10.0.26100.33158
10.0.26100.33158
Microsoft Windows Server 2019<10.0.17763.9020
10.0.17763.9020
Microsoft Windows 11=24H2
10.0.26100.8875
Microsoft Windows 10=21H2
10.0.19044.7548
Microsoft Windows Server 2022<10.0.20348.5386
10.0.20348.5386
Microsoft Windows 10=22H2
10.0.19045.7548
Microsoft Windows 10=21H2
10.0.19044.7548
Microsoft Windows 10=21H2
10.0.19044.7548
Microsoft Windows 10=1809
10.0.17763.9020
Microsoft Windows 10=1809
10.0.17763.9020
Microsoft Windows Server 2019<10.0.17763.9020
10.0.17763.9020
Microsoft Windows 10 1607<10.0.14393.9339
Microsoft Windows 10 1607<10.0.14393.9339
Microsoft Windows 10 1809<10.0.17763.9020
Microsoft Windows 10 1809<10.0.17763.9020
Microsoft Windows 10 21h2<10.0.19044.7548
Microsoft Windows 10 21h2<10.0.19044.7548
Microsoft Windows 10 21h2<10.0.19044.7548
Microsoft Windows 10 22h2<10.0.19045.7548
Microsoft Windows 10 22h2<10.0.19045.7548
Microsoft Windows 10 22h2<10.0.19045.7548
Microsoft Windows 11 24h2<10.0.26100.8875
Microsoft Windows 11 24h2<10.0.26100.8875
Microsoft Windows 11 25h2<10.0.26200.8875
Microsoft Windows 11 25h2<10.0.26200.8875
Microsoft Windows 11 26h1<10.0.28000.2525
Microsoft Windows 11 26h1<10.0.28000.2525
Microsoft Windows Server 2012
Microsoft Windows Server 2012=r2
Microsoft Windows Server 2016<10.0.14393.9339
Microsoft Windows Server 2019<10.0.17763.9020
Microsoft Windows Server 2022<10.0.20348.5386
Microsoft Windows Server 2025<10.0.26100.33158

Remediation

Patch Available

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-54982

Event History

Jul 14, 2026
CVE Published
via Microsoft·02:00 PM
Data Sourced
via Microsoft·02:00 PM
DescriptionSeverityWeakness
Data Sourced
via Microsoft·02:00 PM
Affected Software
Updated
via Microsoft·02:00 PM
Description
CVE Published
via MITRE·05:04 PM
Data Sourced
via MITRE·05:04 PM
DescriptionSeverity
Data Sourced
via NVD·05:17 PM
RemedyDescriptionSeverityWeaknessAffected Software

Frequently Asked Questions

1

What is the severity of CVE-2026-54982?

CVE-2026-54982 has a high severity rating of 8.8.

2

What does CVE-2026-54982 affect?

CVE-2026-54982 affects Microsoft Windows 10, Windows 11, and various Windows Server versions including 2012 R2, 2012, 2016, 2019, and 2025.

3

What type of vulnerability is CVE-2026-54982?

CVE-2026-54982 is classified as an integer underflow vulnerability in the Windows Reliable Multicast Transport Driver.

4

How can I fix CVE-2026-54982?

To fix CVE-2026-54982, ensure your Windows operating system is updated with the latest security patches from Microsoft.

5

What attacks can CVE-2026-54982 potentially enable?

CVE-2026-54982 could allow an unauthorized attacker to execute malicious code over an adjacent network.

Company

Resources

Contact

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