CVE-2026-69781Important
Windows DHCP Client Denial of Service Vulnerability
Assessment
Missing release of memory after effective lifetime in Windows DHCP Client allows an unauthorized attacker to deny service over an adjacent network.
- Severity
- Important
- CVSS base score
- 6.5CVSS:3.1/
AV:A/ AC:L/ PR:N/ UI:N/ S:U/ C:N/ I:N/ A:H/ E:U/ RL:O/ RC:C - Impact
- Denial of Service
- EPSS, next 30 days
- 0.6%Higher than 45.6% of scored CVEs · FIRST model run 26 Sep 2026 · about EPSS
- Exploitability
- Exploitation Unlikely
- Publicly disclosed
- No
- Customer action
- Required: apply the update
- Component
- Windows DHCP Client
- Weakness
- CWE-401: Missing Release of Memory after Effective Lifetime
- Issued by
- Microsoft
- Published
- 8 Sep 2026 · September 2026
- Last revised
- 8 Sep 2026
Updates that fix it
3 KBs| KB | Type | Restart | Applies to | Other CVEs |
|---|---|---|---|---|
| KB5122871 | Security Update | Required | Windows Server 2025, Windows Server 2025 (Server Core installation) | All CVEs in KB5122871 |
| KB5124008 | Security Update | Required | Windows 11 Version 24H2 for ARM64-based Systems, Windows 11 Version 24H2 for x64-based Systems, Windows 11 Version 25H2 for ARM64-based Systems and 1 more | All CVEs in KB5124008 |
| KB5124012 | Security Update | Required | Windows 11 Version 26H1 for ARM64-based Systems, Windows 11 version 26H1 for x64-based Systems | All CVEs in KB5124012 |
Affected products
Windows8 affected products
- Windows 11 Version 24H2 for ARM64-based Systems
- Windows 11 Version 24H2 for x64-based Systems
- Windows 11 Version 25H2 for ARM64-based Systems
- Windows 11 Version 25H2 for x64-based Systems
- Windows 11 Version 26H1 for ARM64-based Systems
- Windows 11 version 26H1 for x64-based Systems
- Windows Server 2025
- Windows Server 2025 (Server Core installation)