CVE-2026-77891: CWE-125: Out-of-bounds Read in Microsoft Windows 10 Version 1607
Description
Out-of-bounds read in Windows DHCP Server allows an authorized attacker to execute code locally.
CVSS v3.1
Score 6.4medium
Affected software
Microsoft
Windows 10 Version 1607
Microsoft
Windows 10 Version 1809
Microsoft
Windows Server 2012
Microsoft
Windows Server 2012 (Server Core installation)
Microsoft
Windows Server 2012 R2
Microsoft
Windows Server 2012 R2 (Server Core installation)
Microsoft
Windows Server 2016
Microsoft
Windows Server 2016 (Server Core installation)
Microsoft
Windows Server 2019
Microsoft
Windows Server 2019 (Server Core installation)
Microsoft
Windows Server 2022
Microsoft
Windows Server 2025
Microsoft
Windows Server 2025 (Server Core installation)
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability (CVE-2026-77891) involves an out-of-bounds read in the Windows DHCP Server component. It affects several Windows 10 versions and Windows Server versions as indicated by the affected version ranges. An attacker with authorized access and high privileges can exploit this flaw to execute code locally on the affected system. The vulnerability has a CVSS 3.1 base score of 6.4, reflecting medium severity. Microsoft has published an official security update to remediate this issue.
Potential Impact
Successful exploitation allows an authorized attacker with high privileges to execute arbitrary code locally on the affected system. This can lead to full compromise of confidentiality, integrity, and availability of the system. However, exploitation requires high privileges and no user interaction is needed.
Mitigation Recommendations
An official fix is available from Microsoft. Users and administrators should apply the security updates provided in the Microsoft advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-77891 to remediate this vulnerability.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- microsoft
- Date Reserved
- 2026-08-21T17:26:55.612Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- official-fix
- Vendor Advisory Urls
- [{"url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-77891","vendor":"Microsoft"}]
Threat ID: 6aa0455aacd9273b49fa9fdc
Added to database: 09/08/2026, 17:26:50 UTC
Last enriched: 10/14/2026, 21:58:12 UTC
Last updated: 10/21/2026, 13:40:31 UTC
Views: 18
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