Vulnerability · Published Sep 8, 2026 · Assigned by microsoft
CVE-2026-70091Windows DNS Denial of Service Vulnerability
Medium 5.9
In plain English
A medium-severity race condition in Windows 10 Version 1607 from Microsoft. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.7% (higher than 52% of all known vulnerabilities).
Severity (CVSS 3.1)5.9Medium
Exploit odds (30 days)0.7%top 48.4% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
Official description
Concurrent execution using shared resource with improper synchronization ('race condition') in Windows DNS allows an unauthorized attacker to deny service over a network.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Microsoft | Windows 10 Version 1607 | 10.0.14393.0 – before 10.0.14393.9512 |
| Microsoft | Windows 10 Version 1809 | 10.0.17763.0 – before 10.0.17763.9245 |
| Microsoft | Windows Server 2012 | 6.2.9200.0 – before 6.2.9200.26349 |
| Microsoft | Windows Server 2012 (Server Core installation) | 6.2.9200.0 – before 6.2.9200.26349 |
| Microsoft | Windows Server 2012 R2 | 6.3.9600.0 – before 6.3.9600.23398 |
| Microsoft | Windows Server 2012 R2 (Server Core installation) | 6.3.9600.0 – before 6.3.9600.23398 |
| Microsoft | Windows Server 2016 | 10.0.14393.0 – before 10.0.14393.9512 |
| Microsoft | Windows Server 2016 (Server Core installation) | 10.0.14393.0 – before 10.0.14393.9512 |
| Microsoft | Windows Server 2019 | 10.0.17763.0 – before 10.0.17763.9245 |
| Microsoft | Windows Server 2019 (Server Core installation) | 10.0.17763.0 – before 10.0.17763.9245 |
| Microsoft | Windows Server 2022 | 10.0.20348.0 – before 10.0.20348.5622 |
| Microsoft | Windows Server 2025 | 10.0.26100.0 – before 10.0.26100.33438 |
| Microsoft | Windows Server 2025 (Server Core installation) | 10.0.26100.0 – before 10.0.26100.33438 |
Weakness: CWE-362 · Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C
References
- Windows DNS Denial of Service Vulnerability vendor-advisory, patch