Windows DNS: Out-of-bounds read enables information disclosure
Summary
Microsoft Windows DNS on affected Windows Server 2016, 2019, 2022 and 2025 contains an out-of-bounds read (CWE-125). An attacker with high privileges on the network can read sensitive memory contents, but cannot change data or stop the service. Internet exposure is unlikely to be the main risk; internal DNS servers and domain controllers are the relevant systems.
Affected
- Windows Server 2016 and 2016 (Server Core installation): 10.0.14393.0 to before 10.0.14393.9688
- Windows Server 2019 and 2019 (Server Core installation): 10.0.17763.0 to before 10.0.17763.9487
- Windows Server 2022: 10.0.20348.0 to before 10.0.20348.5870
- Windows Server 2025 and 2025 (Server Core installation): 10.0.26100.0 to before 10.0.26100.33822
- Windows 10, Windows 11 and Windows Server 2012: Unknown.
Fixed in
- Install the Microsoft security update for the affected Windows Server version, which brings the build to at least the fixed version listed above.
- Fixed builds per CVE record: 10.0.14393.9688, 10.0.17763.9487, 10.0.20348.5870, 10.0.26100.33822.
- KB number: Unknown (MSRC page could not be retrieved).
Workaround
- No vendor workaround published.
- Interim control: restrict access to DNS servers to trusted clients and subnets.
Exploitation
- Not known to be exploited as of 10 November 2026.
- No public proof of concept, CISA KEV listing or GitHub advisory found.
- Rapid7 rates exploitation as less likely.
- CISA SSVC: exploitation none, not automatable, partial technical impact.
Our recommendation
- Patch Windows Server DNS servers and domain controllers in the normal monthly cycle, starting with domain controllers.
- Confirm the fixed build and KB number in the MSRC advisory before rollout.
- Verify that DNS servers are reachable only from internal, trusted networks.
- Do not confuse this with CVE-2026-96972, a separate Windows DNS out-of-bounds read that a third-party site rates 7.5; verify its details separately.
Information from Microsoft (Patch Tuesday November 2026)
- Severity (Microsoft)
- Important
- Impact
- Information disclosure – 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
- CVE Record CVE-2026-96970 www.cve.org
- Microsoft Security Update Guide CVE-2026-96970 msrc.microsoft.com
- VulDB CVE-2026-96970 vuldb.com
- Rapid7 Patch Tuesday November 2026 www.rapid7.com
- OffSeq Radar CVE-2026-96970 radar.offseq.com
- Strix CVE-2026-96970 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, 19:36.
Original description (NVD)
Out-of-bounds read in Windows DNS allows an authorized attacker to disclose information 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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