Windows Remote Desktop Services: Remote code execution via heap overflow
Summary
A heap-based buffer overflow in Windows Remote Desktop Services allows code execution on affected Windows hosts over the network. The CVSS vector requires a network-reachable service and a low-privileged account, with no user interaction needed. Exposed RDS servers with unpatched builds are the main risk for SMEs.
Affected
- Windows 10 Version 1607 (before 10.0.14393.9688)
- Windows 10 Version 1809 (before 10.0.17763.9487)
- Windows 10 Version 21H2 (before 10.0.19044.7846)
- Windows 10 Version 22H2 (before 10.0.19045.7846)
- Windows 11 Version 23H2 (before 10.0.22631.7711)
- Windows 11 Version 24H2 (before 10.0.26100.9974)
- Windows 11 Version 25H2 (before 10.0.26200.9974)
- Windows 11 Version 26H1 (before 10.0.28000.3501)
- Windows 11 Version 26H2 (before 10.0.26300.9974)
- Windows Server 2016 incl. Server Core (before 10.0.14393.9688)
- Windows Server 2019 incl. Server Core (before 10.0.17763.9487)
- Windows Server 2022 (before 10.0.20348.5870)
- Windows Server 2025 and 2012/2012 R2: Unknown (not confirmed in the CNA record; third-party sources conflict)
Fixed in
- Fixed in Microsoft's November 2026 security updates. Exact KB per OS: Unknown, verify on MSRC.
- Fixed builds per the CVE record: see the affected list above.
Workaround
No vendor workaround known.
Exploitation
- Not known to be exploited in the wild (no CISA KEV entry found at time of research).
- CISA SSVC: Exploitation none, Automatable no, Technical Impact total.
- No public proof-of-concept found.
Our recommendation
- Inventory Windows servers and workstations with Remote Desktop Services enabled and identify any internet-facing RDP.
- Install the November 2026 cumulative update on all affected systems; confirm the KB for each OS on the MSRC advisory.
- Until patched, remove RDP exposure from the internet and allow access only via VPN or an RD Gateway with MFA; keep Network Level Authentication enabled.
- Review accounts with RDS access and reset credentials that may be reused or phished.
- Monitor for re-checks of CISA KEV and the NVD entry, which were still awaiting analysis at publication.
Information from Microsoft (Patch Tuesday November 2026)
- Severity (Microsoft)
- Important
- Impact
- Remote code execution – Windows Remote Desktop Services
- Status on Patch Tuesday
- Neither exploited nor publicly disclosed
- Exploitability assessment
- Exploitation less likely
- Product family
- Windows, Windows ESU (Extended Security Updates)
- Updates (KB)
- KB5131291, KB5131085, KB5131096, KB5131090, KB5131087, KB5132061
Public exploits
PoC-in-GitHub, Metasploit and Exploit-DB list nothing for this CVE.
Research sources
- Microsoft Security Update Guide: CVE-2026-108401 msrc.microsoft.com
- CVE Record: CVE-2026-108401 www.cve.org
- Senserva KB 5132061 senserva.com
- Strix CVE-2026-108401 www.strix.ai
- Microsoft Q&A: Windows Remote Desktop Services privilege escalation learn.microsoft.com
Researched and written up in English and German by an AI (Claude by Anthropic) based on NVD, CISA, EPSS and the sources listed. The vendor information is authoritative. Researched on 10 Nov 2026, 23:58.
Original description (NVD)
Heap-based buffer overflow in Windows Remote Desktop Services allows an authorized attacker to execute code over a network.
NVD references (1)
Sources
The tracker combines official, freely usable data sources – updated continuously:
- NVD (NIST) – CVEs, rating (CVSS), affected products
- CISA KEV – vulnerabilities confirmed by CISA as actively exploited
- CISA Vulnrichment – CISA assessment (SSVC) in the official CVE record
- FIRST EPSS – probability of exploitation
- Microsoft MSRC – Patch Tuesday: vulnerabilities, severity, updates
- PoC-in-GitHub – public proof-of-concept repositories
- Metasploit (Rapid7) – modules of the Metasploit Framework
- Exploit-DB (OffSec) – archive of public exploits (links only)
- Patch days: official vendor pages (linked per vendor) (Vendor patch days)
This product uses data from the NVD API but is not endorsed or certified by the NVD. EPSS data © FIRST.org.
Affected? We can help.
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