## Microsoft Windows Projected File System Race Condition Vulnerability (CVE-2026-27927) Exposes Local Privilege Escalation Risk
A newly disclosed high-severity vulnerability in the Windows Projected File System (ProjFS) creates a direct path for local privilege escalation. Tracked as CVE-2026-27927 and GHSA-xmhh-m2j3-cr44, the flaw is a race condition (CWE-362) that allows an authorized attacker with initial local access to elevate their privileges on the system. With a CVSS score of 7.8, the vulnerability is rated high severity, posing a significant risk to confidentiality, integrity, and availability.

The core of the issue lies in improper synchronization within ProjFS, a Windows feature that allows applications to project a view of a file system into a folder. The race condition enables an attacker to exploit concurrent execution using a shared resource, potentially gaining higher-level system permissions. This type of flaw is particularly dangerous as it can be leveraged by malware or a malicious insider to break out of restricted user contexts and gain control over the operating system.

While the exploit requires local access (AV:L) and low attack complexity (AC:L), its impact is broad, affecting any system running a vulnerable version of Windows with ProjFS enabled. The publication of the advisory by both Microsoft and GitHub prompts immediate scrutiny from enterprise security teams and system administrators. Organizations must now prioritize applying the relevant Microsoft security update to mitigate the risk of attackers using this flaw to move laterally or establish persistence within a network.
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- **Source**: GitHub Issues
- **Sector**: The Lab
- **Tags**: CVE-2026-27927, Windows, Privilege Escalation, Race Condition, ProjFS
- **Credibility**: unverified
- **Published**: 2026-04-15 03:22:30
- **ID**: 64789
- **URL**: https://whisperx.ai/en/intel/64789