CVE-2026-96176: Windows DNS Denial of Service Vulnerability
CVE-2026-96176 is a denial of service vulnerability in Windows DNS, rated Important by Microsoft, with a CVSS 3.1 base score of 7.5 (High). An attacker can exploit it remotely over the network, without any privileges and without user interaction. Microsoft has not reported exploitation in the wild and rates exploitation as less likely. Microsoft released the fix on 10 November 2026 in the November 2026 Patch Tuesday, delivered through 6 security updates (KB5131087, KB5132061, KB5132043, KB5131080 and more). It affects 12 products in 1 product family (Windows).
Key facts
- CVE ID
- CVE-2026-96176
- Severity
- High CVSS 7.5
- Microsoft severity
- Important
- Impact
- Denial of Service
- Exploited in the wild
- No
- Publicly disclosed
- No
- Exploitation likelihood
- Less Likely
- CISA KEV
- Not listed
- Released
- Last updated
- Patch Tuesday
- November 2026 Patch Tuesday
- Product families
- Windows
CVSS score and vector
Microsoft scores CVE-2026-96176 at 7.5 (temporal 6.5) using CVSS 3.1. Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C
| Metric | Value |
|---|---|
| Attack vector | Network |
| Attack complexity | Low |
| Privileges required | None |
| User interaction | None |
| Scope | Unchanged |
| Confidentiality impact | None |
| Integrity impact | None |
| Availability impact | High |
| Exploit code maturity | Unproven |
| Remediation level | Official fix |
| Report confidence | Confirmed |
Description
Missing release of memory after effective lifetime in Windows DNS allows an unauthorized attacker to deny service over a network.
Affected products (12)
Windows
| Product | Security update | Type | Fixed build | Restart |
|---|---|---|---|---|
| Windows 11 Version 23H2 for x64-based Systems | KB5131087 | Security Update | 10.0.22631.7711 | Yes |
| Windows 11 Version 23H2 for ARM64-based Systems | KB5131087 | Security Update | 10.0.22631.7711 | Yes |
| Windows 11 Version 24H2 for x64-based Systems | KB5132061 KB5132043 | Security Update Security Update | 10.0.26100.9974 10.0.26100.9911 | Yes No |
| Windows 11 Version 24H2 for ARM64-based Systems | KB5132061 KB5132043 | Security Update Security Update | 10.0.26100.9974 10.0.26100.9911 | Yes No |
| Windows 11 Version 25H2 for x64-based Systems | KB5132043 | Security Update | 10.0.26200.9911 | No |
| Windows 11 Version 25H2 for ARM64-based Systems | KB5132043 | Security Update | 10.0.26200.9911 | No |
| Windows 11 Version 26H2 for x64-based Systems | KB5132043 | Security Update | 10.0.26300.9911 | No |
| Windows 11 Version 26H2 for ARM64-based Systems | KB5132043 | Security Update | 10.0.26300.9911 | No |
| Windows Server 2025 | KB5131080 KB5131077 | Security Update Security Hotpatch Update | 10.0.26100.33822 10.0.26100.33730 | Yes No |
| Windows Server 2025 (Server Core installation) | KB5131080 KB5131077 | Security Update Security Hotpatch Update | 10.0.26100.33822 10.0.26100.33730 | Yes No |
| Windows 11 version 26H1 for x64-based Systems | KB5132059 | Security Update | 10.0.28000.3501 | Yes |
| Windows 11 Version 26H1 for ARM64-based Systems | KB5132059 | Security Update | 10.0.28000.3501 | Yes |
Security updates (6)
Revision history
| Version | Date | Description |
|---|---|---|
| 1.0 | Information published. |