Windows DNS Server: Elevation of privilege via link following
Summary
A flaw in the Windows DNS Server component allows an authorized attacker on the network to elevate privileges. The cause is improper link resolution before file access (CWE-59). No user interaction is required, but the attacker must already hold high privileges, so this is mainly a risk after an initial compromise. A DNS server on a domain controller can affect the whole Active Directory.
Affected
- Windows Server 2016 and Windows Server 2016 (Server Core installation): 10.0.14393.0 before 10.0.14393.9688
- Windows Server 2019 and Windows Server 2019 (Server Core installation): 10.0.17763.0 before 10.0.17763.9487
- Windows Server 2022: 10.0.20348.0 before 10.0.20348.5870
- Windows Server 2025 and Windows Server 2025 (Server Core installation): 10.0.26100.0 before 10.0.26100.33822
Fixed in
- Fixed in Microsoft's November 2026 security updates.
- Fixed builds per the CVE record: 10.0.14393.9688, 10.0.17763.9487, 10.0.20348.5870 and 10.0.26100.33822 or later.
- KB numbers: Unknown. Check the MSRC advisory.
Workaround
- Unknown. No mitigation found in the sources.
Exploitation
- No evidence of exploitation in the wild.
- No public proof of concept found.
- CISA SSVC: exploitation none, not automatable, technical impact total.
Our recommendation
- Install the November 2026 security updates on Windows Server 2016, 2019, 2022 and 2025, starting with domain controllers and DNS servers.
- Confirm the KB and build numbers on the MSRC advisory before rollout.
- Limit privileged access to DNS servers and domain controllers, and monitor for unusual privilege changes.
- Make sure DNS servers are not reachable from untrusted networks.
Information from Microsoft (Patch Tuesday November 2026)
- Severity (Microsoft)
- Important
- Impact
- Elevation of privilege – Windows DNS
- 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, KB5131090, KB5131080, KB5131077
Public exploits
PoC-in-GitHub, Metasploit and Exploit-DB list nothing for this CVE.
Research sources
- Microsoft Security Update Guide (MSRC advisory) msrc.microsoft.com
- CVE Record (CNA: Microsoft) www.cve.org
- Strix: CVE-2026-105520 www.strix.ai
- VulDB entry vuldb.com
- BleepingComputer: November 2026 Patch Tuesday www.bleepingcomputer.com
- SecurityOnline: Critical Windows vulnerabilities November 2026 securityonline.info
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, 06:52.
Original description (NVD)
Improper link resolution before file access ('link following') in Windows DNS allows an authorized attacker to elevate privileges 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.
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