Executive brief
A security vulnerability exists in the Windows Network File System, a component used to share files across different operating systems. An attacker who already has basic access to a computer could exploit this flaw to gain full administrative control over the system. This could lead to unauthorized access to sensitive data, installation of malicious software, or disruption of business operations.
Technical details
This vulnerability is a heap-based buffer overflow (CWE-122) within the Windows Network File System (NFS) driver, reportedly triggered by a numeric truncation error (CWE-197). An attacker with local access and low-level privileges (PR:L) can exploit this flaw to execute code in kernel mode. Successful exploitation allows for full local privilege escalation to SYSTEM. The attack vector is local and does not require user interaction. Microsoft has released security updates to address this issue across affected Windows and Windows Server versions.
Affected products
- Microsoft Windows 10 Version 1607 10.0.14393.0 to 10.0.14393.9339
- Microsoft Windows 10 Version 1809 10.0.17763.0 to 10.0.17763.9020
- Microsoft Windows 10 Version 21H2 10.0.19044.0 to 10.0.19044.7548
- Microsoft Windows 10 Version 22H2 10.0.19045.0 to 10.0.19045.7548
- Microsoft Windows 11 Version 24H2 10.0.26100.0 to 10.0.26100.8875
- Microsoft Windows Server 2012 6.2.9200.0 to 6.2.9200.26226
Timeline
- 2026-07-14: disclosed
- 2026-07-14: advisory