CVE-2026-62820CriticalRevised 8 Sep
Windows DNS Server Remote Code Execution Vulnerability
Assessment
Concurrent execution using shared resource with improper synchronization ('race condition') in Windows DNS allows an unauthorized attacker to execute code over a network.
- Severity
- Critical
- CVSS base score
- 8.1CVSS:3.1/
AV:N/ AC:H/ PR:N/ UI:N/ S:U/ C:H/ I:H/ A:H/ E:U/ RL:O/ RC:C - Impact
- Remote Code Execution
- EPSS, next 30 days
- 0.5%Higher than 43.3% of scored CVEs · FIRST model run 26 Sep 2026 · about EPSS
- Exploitability
- Exploitation Less Likely
- Publicly disclosed
- No
- Customer action
- Required: apply the update
- Component
- Windows DNS
- Weakness
- CWE-362: Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')
- Issued by
- Microsoft
- Published
- 11 Aug 2026 · August 2026
- Last revised
- 8 Sep 2026Updated software table to remove clients versions because this vulnerability only impacts Windows Servers. This is an informational change only.
Updates that fix it
6 KBs| KB | Type | Restart | Applies to | Other CVEs |
|---|---|---|---|---|
| KB5120228 | Security Hotpatch Update | Required | Windows Server 2025, Windows Server 2025 (Server Core installation) | All CVEs in KB5120228 |
| KB5120229 | Security Hotpatch Update | Required | Windows Server 2022, Windows Server 2022 (Server Core installation) | All CVEs in KB5120229 |
| KB5120233 | Security Update | Required | Windows Server 2025, Windows Server 2025 (Server Core installation) | All CVEs in KB5120233 |
| KB5120238 | Security Update | Required | Windows Server 2019, Windows Server 2019 (Server Core installation) | All CVEs in KB5120238 |
| KB5120242 | Security Update | Required | Windows Server 2022, Windows Server 2022 (Server Core installation) | All CVEs in KB5120242 |
| KB5120418 | Security Update | Required | Windows Server 2016, Windows Server 2016 (Server Core installation) | All CVEs in KB5120418 |
Affected products
Windows8 affected products
- Windows Server 2016
- Windows Server 2016 (Server Core installation)
- Windows Server 2019
- Windows Server 2019 (Server Core installation)
- Windows Server 2022
- Windows Server 2022 (Server Core installation)
- Windows Server 2025
- Windows Server 2025 (Server Core installation)