High MSRC-CVE-2026-84017 1 CVE

Windows Routing and Remote Access Service (RRAS) Denial of Service Vulnerability

Published Oct 13, 2026 · Updated Oct 13, 2026

Vendor: Microsoft

Summary

Impact: Denial of Service. Microsoft rating: Important. Not known to be exploited — Exploitation Unlikely. Customer action: Required.

Details

Security updates
10.0.17763.9376 — https://support.microsoft.com/help/5126651
10.0.20348.5761 — https://support.microsoft.com/help/5126655
10.0.19044.7807 — https://support.microsoft.com/help/5126657
10.0.26100.33650 — https://support.microsoft.com/help/5126646
10.0.26200.9711 — https://support.microsoft.com/help/5127648
10.0.22631.7652 — https://support.microsoft.com/help/5126653
10.0.28000.3231 — https://support.microsoft.com/help/5127646
10.0.14393.9612 — https://support.microsoft.com/help/5126868
6.2.9200.26434 — https://support.microsoft.com/help/5126835
6.3.9600.23470 — https://support.microsoft.com/help/5126836

Vulnerabilities 1

High 7.5

CVE-2026-84017

Windows Routing and Remote Access Service (RRAS) Denial of Service Vulnerability

Null pointer dereference in Windows Routing and Remote Access Service (RRAS) allows an unauthorized attacker to deny service over a network.

Microsoft Windows Server 2019 Windows Server 2019 (Server Core installation) Windows 10 Version 1809 Windows

Oct 13, 2026

Revision history

2026-10-13 #1
Information published.

References

CVE-2026-84017 Windows Routing and Remote Access Service (RRAS) Denial of Service Vulnerability - HTML
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-84017
Microsoft Exploitability Index
https://www.microsoft.com/en-us/msrc/exploitability-index?rtc=1
Microsoft Support Lifecycle
https://support.microsoft.com/lifecycle
Common Vulnerability Scoring System
https://www.first.org/cvss