CVE-2026-65784 in Windows
Summary
by MITRE • 08/12/2026
Out-of-bounds read in Windows NTFS allows an authorized attacker to disclose information locally.
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Analysis
by VulDB Data Team • 08/12/2026
This vulnerability represents a critical out-of-bounds read flaw within the Windows NTFS file system implementation that enables authenticated local attackers to potentially extract sensitive information from memory locations beyond the intended data boundaries. The technical nature of this issue stems from insufficient input validation and boundary checking mechanisms within the ntfs.sys kernel driver component responsible for managing NTFS file system operations. When processing specific file system requests or metadata operations, the driver fails to properly validate array indices or buffer limits, allowing malicious code to read memory contents that should remain inaccessible to regular userspace processes.
The operational impact of this vulnerability extends beyond simple information disclosure as it provides attackers with potential access to sensitive kernel memory structures, including credentials, encryption keys, or other confidential data stored in memory regions adjacent to the affected buffers. Attackers leveraging this flaw can perform arbitrary memory reads through local exploitation techniques that manipulate file system operations to trigger the out-of-bounds condition. This type of vulnerability falls under the CWE-129 category for Improper Validation of Array Index and aligns with ATT&CK technique T1003 for Credential Dumping, as the disclosed information could include authentication credentials or security tokens.
The exploitation requires local system access and typically involves crafting specific file system operations that cause the ntfs.sys driver to access memory beyond allocated buffers. This vulnerability represents a significant risk in environments where local privilege escalation is already possible, as the information disclosure can serve as a stepping stone for further attacks. The flaw demonstrates poor defensive programming practices within kernel space code and highlights the importance of rigorous input validation even in trusted system components.
Security mitigations should focus on implementing proper boundary checks and array index validation within the ntfs.sys driver code, alongside regular security updates from Microsoft that address the specific memory access violations. System administrators should ensure timely patch deployment and consider implementing additional monitoring for unusual file system operations that might indicate exploitation attempts. The vulnerability underscores the critical need for secure coding practices in kernel-level components and emphasizes the importance of comprehensive code review processes to identify similar out-of-bounds access patterns that could lead to more severe security consequences including privilege escalation or system compromise.