Windows Remote Access API: Local privilege escalation via untrusted search path

Summary

The Windows Remote Access API, the interface behind Windows remote access features such as VPN and RAS/RRAS, contains an untrusted search path weakness (CWE-426). An authorized local attacker with a low-privilege account can use it to elevate privileges on the affected host. No user interaction is required, and the CVSS base score is 7.8 (High). The vulnerability is not directly exploitable from the internet.

Affected

• Windows 10 Version 1607: 10.0.14393.0 to before 10.0.14393.9688
• Windows 10 Version 1809: 10.0.17763.0 to before 10.0.17763.9487
• Windows 10 Version 21H2: 10.0.19044.0 to before 10.0.19044.7846
• Windows 10 Version 22H2: 10.0.19045.0 to before 10.0.19045.7846
• Windows 11 Version 23H2: 10.0.22631.0 to before 10.0.22631.7711
• Windows 11 Version 24H2: 10.0.26100.0 to before 10.0.26100.9974
• Windows 11 Version 25H2: 10.0.26200.0 to before 10.0.26200.9974
• Windows 11 Version 26H1: 10.0.28000.0 to before 10.0.28000.3501
• Windows 11 Version 26H2: 10.0.26300.0 to before 10.0.26300.9974
• Windows Server 2016 (including Server Core): 10.0.14393.0 to before 10.0.14393.9688
• Windows Server 2019 (including Server Core): 10.0.17763.0 to before 10.0.17763.9487
• Windows Server 2022: 10.0.20348.0 to before 10.0.20348.5870
• Note: third-party data lists additional builds that are not confirmed by the CVE record. Check the MSRC advisory for the complete list.

Fixed in

• Install the November 2026 cumulative update for each affected product (Patch Tuesday, 10 November 2026).
• Fixed builds are the versions listed in the CVE record as the first unaffected build (for example 10.0.14393.9688 or later for Windows 10 1607 and Windows Server 2016).
• KB article numbers: Unknown. Take them from the MSRC advisory.

Workaround

Unknown. No mitigation or workaround was found in the sources. Check the 'Mitigations' and 'Workarounds' sections of the MSRC advisory.

Exploitation

• No evidence of exploitation in the wild was found.
• CVE.org rates exploit maturity as Unproven (E:U), with report confidence Confirmed (RC:C).
• Microsoft's exploitability index lists Exploitation More Likely (per Tenable). This is an assessment, not evidence of exploitation.
• Public proof-of-concept code: Unknown. Not found in the searches performed.
• CISA KEV status: Unknown. Not checked directly.

Our recommendation

• Install the November 2026 security update on all affected systems, prioritising servers, RDS/terminal servers and shared multi-user workstations.
• Check the MSRC advisory for mitigations and confirm the affected builds for each system.
• Restrict local logon rights and remove unnecessary local accounts, since the attacker needs a low-privilege local account.
• Monitor for CISA KEV additions and public exploit code, and apply the patch in the same cycle as the other critical November 2026 updates.

Public exploits iAttack code is publicly available (PoC on GitHub, Metasploit or Exploit-DB).

PoC-in-GitHub, Metasploit and Exploit-DB list nothing for this CVE.

Research sources

• Microsoft Security Update Guide (MSRC) msrc.microsoft.com
• Microsoft Security Update Guide (en-US) msrc.microsoft.com
• CVE.org CVE Record www.cve.org
• Tenable: Microsoft November 2026 Patch Tuesday www.tenable.com
• Qualys: Microsoft Patch Tuesday November 2026 review blog.qualys.com
• Cisco Talos: Microsoft Patch Tuesday November 2026 blog.talosintelligence.com
• Strix.ai CVE-2026-119853 (third-party, version data unconfirmed) www.strix.ai

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 11 Nov 2026, 03:46.