CVE-2026-69731 in Windows
Summary
by MITRE • 09/09/2026
Heap-based buffer overflow in HID class driver allows an authorized attacker to elevate privileges locally.
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Analysis
by VulDB Data Team • 09/09/2026
The vulnerability described involves a heap-based buffer overflow within the Human Interface Device (HID) class driver, which serves as a critical component of the operating system's input subsystem. This specific flaw arises from improper validation or bounds checking when processing data received from HID-compliant devices such as keyboards, mice, game controllers, and other peripheral inputs. Because the HID driver operates at a high level in the kernel with significant privileges, any memory corruption within this module can have severe consequences for system integrity and security posture. The heap-based nature of the overflow indicates that the vulnerability occurs during dynamic memory allocation routines, where an attacker can manipulate pointers or overwrite adjacent memory structures to alter program execution flow.
An authorized local attacker who has already gained access to the system through legitimate credentials can exploit this flaw to achieve privilege escalation. By crafting malicious HID input reports containing oversized or malformed data payloads, the attacker triggers the buffer overflow condition within the kernel space. This allows for arbitrary code execution with the privileges of the SYSTEM account or other high-privilege contexts depending on the specific operating environment and driver implementation details. The ability to execute code in kernel mode effectively bypasses standard user-level security controls, granting the attacker full control over the affected system including access to sensitive data, installation of persistent malware, and lateral movement within a networked environment.
From an industry standards perspective, this vulnerability aligns with Common Weakness Enumeration (CWE) identifiers such as CWE-120 Buffer Copy without Checking Size of Input Classic Heap-based buffer overflow and potentially CWE-787 Out-of-bounds Write if the overwrite affects critical data structures beyond simple memory corruption. In terms of tactical mapping to the MITRE ATT&CK framework, this exploit scenario corresponds to techniques under Privilege Escalation such as T1068 Exploitation for Privilege Escalation and specifically relates to kernel exploitation vectors often categorized under Local Application Execution or Driver-level exploits. The attack vector is classified as local with low complexity due to the requirement of prior authentication, yet the impact remains critical given the resulting elevation to system-level privileges.
Mitigation strategies must focus on both immediate remediation and long-term architectural improvements. Immediate action should involve applying vendor-provided security patches that address the specific bounds checking deficiencies in the HID class driver codebase. Organizations should prioritize patching systems where such drivers are actively used, particularly those exposed to untrusted peripheral devices or environments with multiple user accounts. Additionally, implementing strict input validation and fuzz testing during development phases can prevent similar heap-based vulnerabilities from being introduced into critical system components. Security teams should also consider deploying endpoint detection and response solutions capable of identifying anomalous kernel-level memory access patterns that may indicate exploitation attempts in progress.