Microsoft Windows DNS Server: Information disclosure via out-of-bounds read

Summary

An out-of-bounds read in the Windows DNS Server role allows an authorized attacker to disclose information over the network. The CVSS 3.1 vector (AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N) shows low complexity, low privileges, no user interaction and an impact on confidentiality only. The attacker therefore needs valid credentials or an authorized position, and the disclosed data is limited to memory contents. The main risk lies with internal DNS servers, domain controllers and file servers.

Affected

• Windows 10 Version 1607 (and Windows Server 2016): 10.0.14393.0 to < 10.0.14393.9612
• Windows 10 Version 1809: 10.0.17763.0 to < 10.0.17763.9376
• Windows 10 Version 21H2: 10.0.19044.0 to < 10.0.19044.7807
• Windows 10 Version 22H2: 10.0.19045.0 to < 10.0.19045.7807
• Windows 11 Version 23H2: 10.0.22631.0 to < 10.0.22631.7652
• Windows 11 Version 24H2: 10.0.26100.0 to < 10.0.26100.9711
• Windows 11 Version 25H2: 10.0.26200.0 to < 10.0.26200.9711
• Windows 11 Version 26H1: 10.0.28000.0 to < 10.0.28000.3231
• Windows 11 Version 26H2: 10.0.26300.0 to < 10.0.26300.9711
• Windows Server 2012 (incl. Server Core): 6.2.9200.0 to < 6.2.9200.26434
• Windows Server 2012 R2 (incl. Server Core): 6.3.9600.0 to < 6.3.9600.23470

Fixed in

• Windows 10 1607 / Server 2016: build 10.0.14393.9612 or later
• Windows 10 1809: build 10.0.17763.9376 or later
• Windows 10 21H2: build 10.0.19044.7807 or later
• Windows 10 22H2: build 10.0.19045.7807 or later
• Windows 11 23H2: build 10.0.22631.7652 or later
• Windows 11 24H2 / 25H2 / 26H2: build 10.0.26100.9711 / 10.0.26200.9711 / 10.0.26300.9711 or later
• Windows 11 26H1: build 10.0.28000.3231 or later
• Windows Server 2012: build 6.2.9200.26434 or later
• Windows Server 2012 R2: build 6.3.9600.23470 or later
• KB number: Unknown.

Workaround

Unknown.

Exploitation

• Exploitation in the wild: not confirmed. No entry in the CISA KEV catalog was found.
• CISA SSVC: exploitation none, not automatable, partial technical impact.
• Public proof of concept: none found.

Our recommendation

• Confirm the KB number and fixed build for each system on the Microsoft Security Update Guide.
• Patch affected DNS servers first, starting with internet-facing servers and domain controllers.
• Check whether Windows 10 1607 or Windows Server 2012 systems are still in use and plan their replacement, as they may no longer receive security updates. Verify the lifecycle dates with Microsoft.
• Restrict DNS server management and recursion to trusted networks and review accounts with DNS administration rights.
• Monitor DNS server logs for unusual queries or access.

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: CVE-2026-108129 msrc.microsoft.com
• Vulners: CVE-2026-108129 (CVE list) vulners.com
• Threatint: CVE-2026-108129 cve.threatint.com
• Strix: CVE-2026-108129 www.strix.ai
• Tenable plugin 365473 (Server 2025 update) www.tenable.com
• Tenable plugin 365466 (Server 2012 update) www.tenable.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 5 Nov 2026, 11:31.