CVE-2026-62887 in Windows
Summary
by MITRE • 08/11/2026
Out-of-bounds read in Windows NTFS allows an authorized attacker to disclose information locally.
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Analysis
by VulDB Data Team • 08/11/2026
This vulnerability represents a critical out-of-bounds read flaw within the Windows NTFS file system implementation that enables authenticated local attackers to extract sensitive information from memory locations beyond the intended buffer boundaries. The technical nature of this issue stems from insufficient input validation and boundary checking mechanisms within the NTFS driver components responsible for handling file system operations. When legitimate user processes interact with NTFS file systems, particularly during file access, modification, or metadata retrieval operations, the vulnerable code paths fail to properly validate array indices or buffer limits before accessing memory locations. This fundamental flaw allows an attacker who has already established a valid user session on the target system to craft specific file operations that trigger the out-of-bounds memory access pattern.
The operational impact of this vulnerability extends beyond simple information disclosure as it can potentially expose sensitive kernel memory contents including cryptographic keys, credential information, or other confidential data structures that reside in memory spaces accessible through the NTFS subsystem. Attackers can leverage this primitive to gather intelligence about the system's internal state, potentially aiding in more sophisticated attacks such as privilege escalation or lateral movement within the network environment. The vulnerability is particularly concerning because it operates at the file system level where attackers already possess legitimate access rights, making detection more challenging and exploitation more feasible compared to remote attack vectors.
From a cybersecurity perspective, this issue aligns with CWE-129, which specifically addresses insufficient validation of length of input buffers, and represents a classic example of memory safety vulnerabilities that have plagued operating system implementations for decades. The ATT&CK framework categorizes this type of vulnerability under the T1068 technique for 'Exploitation for Privilege Escalation' since it can serve as an initial foothold for more advanced exploitation attempts. The attack surface is primarily limited to local system access but the potential for information leakage makes it a significant concern for enterprise environments where privileged accounts might be compromised. Organizations should prioritize patching this vulnerability through Microsoft's regular security updates, as the flaw exists within core operating system components that are essential for normal system operation and cannot be easily mitigated through network-level controls or application firewalls.
The root cause analysis reveals that this vulnerability likely originates from inadequate bounds checking in NTFS driver code handling file metadata operations or directory traversal functions. When processing file system requests, the system fails to validate that array indices used for accessing file system structures remain within legitimate memory boundaries, allowing attackers to manipulate input parameters to trigger the out-of-bounds read condition. This type of vulnerability demonstrates the ongoing challenges in ensuring memory safety within complex operating system kernels where decades of code evolution and feature additions have created numerous potential attack vectors. The exploitability requires local authentication but does not necessitate elevated privileges, making it particularly dangerous in multi-user environments or systems where user accounts might be compromised through social engineering or other attack vectors.
Security practitioners should implement comprehensive monitoring for unusual file system access patterns that might indicate exploitation attempts, while also ensuring regular patch management processes are in place to address such vulnerabilities promptly. The vulnerability's classification as a local information disclosure issue means that traditional network-based security controls provide limited protection, emphasizing the importance of endpoint protection measures and privileged access management. Organizations should conduct risk assessments to determine which systems are most vulnerable based on their usage patterns and security posture, particularly focusing on systems where multiple users might have legitimate access to NTFS file systems. The remediation process requires careful consideration of patch deployment timing and rollback procedures since NTFS is fundamental to system operation and any disruption could impact critical business functions.
This vulnerability exemplifies the challenges faced by cybersecurity professionals in defending against memory safety issues that persist despite decades of research into secure programming practices and automated vulnerability detection tools. The persistence of such flaws in core operating system components highlights the need for continuous security assessments, proper code review processes, and investment in secure development lifecycle practices. Organizations should also consider implementing additional security controls such as memory protection mechanisms, kernel-mode code integrity checks, and regular security audits to identify and remediate similar vulnerabilities before they can be exploited by malicious actors. The attack surface remains limited to authenticated local access but the potential for information leakage makes this vulnerability particularly concerning for environments where system compromise might occur through other attack vectors.