CVE-2026-58640 in Windows
Summary
by MITRE • 07/14/2026
Heap-based buffer overflow in Windows NTFS allows an authorized attacker to execute code locally.
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Analysis
by VulDB Data Team • 07/14/2026
This vulnerability represents a critical heap-based buffer overflow flaw within the Windows NT File System implementation that enables local privilege escalation through unauthorized code execution. The vulnerability stems from inadequate bounds checking during memory allocation operations within the ntfs.sys kernel driver responsible for NTFS file system operations. When legitimate user processes interact with NTFS volumes, particularly during file creation, modification, or metadata handling operations, malformed input data can trigger improper memory management that overflows heap allocated buffers.
The technical exploitation occurs when an authenticated local attacker crafts specific file system operations that cause the ntfs.sys driver to allocate insufficient memory for processing certain file attributes or directory entries. This memory corruption directly impacts the heap management structures, potentially allowing attackers to overwrite critical function pointers, return addresses, or other control data within the kernel memory space. The vulnerability is classified under CWE-121 heap-based buffer overflow, which falls under the broader category of memory safety issues that have historically enabled numerous privilege escalation attacks in operating system kernels.
From an operational perspective, this flaw significantly impacts Windows systems running NTFS file systems as it provides a pathway for attackers who already possess valid user credentials to elevate their privileges to kernel level execution. The attack vector requires local system access and authentication, making it less suitable for remote exploitation but still highly dangerous in environments where insider threats exist or where initial access has been achieved through other means. The vulnerability affects multiple Windows versions including windows 10, windows server 2016, and later releases that utilize NTFS as their primary file system.
The attack pattern aligns with tactics described in the attack tree framework under techniques such as privilege escalation and code injection. Attackers can leverage this vulnerability to execute arbitrary code with kernel-level privileges, potentially enabling them to bypass security controls, establish persistent access, or extract sensitive data from protected system components. The exploitation typically involves creating specific file system structures that trigger the overflow condition, followed by careful manipulation of the heap memory layout to achieve code execution.
Mitigation strategies include applying Microsoft security patches immediately upon release, as these vulnerabilities are typically addressed through kernel memory management updates and enhanced input validation routines. System administrators should implement least privilege principles and monitor for unusual file system activity patterns that might indicate exploitation attempts. Additional protective measures include enabling kernel address space layout randomization, using exploit protection mechanisms, and maintaining updated intrusion detection systems to identify potential exploitation activities targeting this class of vulnerability. The remediation process should prioritize immediate patch deployment while implementing monitoring protocols to detect any attempted exploitation attempts against vulnerable systems.