CVE-2019-0682 in Windows
Summary
by MITRE
An elevation of privilege vulnerability exists due to an integer overflow in Windows Subsystem for Linux, aka 'Windows Subsystem for Linux Elevation of Privilege Vulnerability'. This CVE ID is unique from CVE-2019-0689, CVE-2019-0692, CVE-2019-0693, CVE-2019-0694.
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Analysis
by VulDB Data Team • 08/01/2023
The vulnerability identified as CVE-2019-0682 represents a critical elevation of privilege flaw within the Windows Subsystem for Linux (WSL) component of Microsoft Windows operating systems. This issue specifically affects the subsystem's handling of integer values during memory management operations, creating a pathway for malicious actors to escalate their privileges from standard user level to administrative access. The vulnerability stems from improper validation of integer values within the WSL kernel components that manage process execution and memory allocation for Linux-compatible applications running on Windows. The flaw manifests when the subsystem processes certain memory allocation requests that trigger an integer overflow condition, potentially allowing attackers to manipulate memory structures and execute arbitrary code with elevated privileges.
The technical exploitation of this vulnerability involves leveraging the integer overflow to corrupt memory management structures within the WSL subsystem. When legitimate applications request memory resources, the subsystem's integer handling logic fails to properly validate the size parameters, causing arithmetic overflow that can overwrite adjacent memory regions. This memory corruption can be manipulated to redirect execution flow or modify critical system data structures, ultimately enabling privilege escalation. The vulnerability is particularly concerning because it operates at the kernel level within the WSL subsystem, meaning that successful exploitation bypasses standard user-mode security controls and can potentially provide attackers with full administrative access to the underlying Windows system. The integer overflow occurs in the subsystem's memory management functions that handle process creation and resource allocation for Linux applications running within the Windows environment.
The operational impact of CVE-2019-0682 extends beyond simple privilege escalation, as it can enable attackers to establish persistent access to compromised systems while potentially bypassing modern security controls such as User Access Control and application whitelisting mechanisms. Attackers can leverage this vulnerability to gain unauthorized access to sensitive data, modify system configurations, install malicious software, or establish backdoors for continued access. The vulnerability affects Windows 10 versions prior to the July 2019 security updates, with the WSL component being particularly targeted due to its integration with Windows kernel components. This flaw demonstrates a fundamental weakness in the subsystem's input validation mechanisms and highlights the challenges of maintaining security boundaries between Windows kernel space and Linux emulation environments. The vulnerability's exploitation requires minimal privileges initially, as it can be triggered through normal WSL usage, making it particularly dangerous in environments where users have standard account access but require elevated privileges for legitimate administrative tasks.
Mitigation strategies for CVE-2019-0682 focus primarily on applying Microsoft's security patches released in July 2019, which address the integer overflow condition in the WSL subsystem's memory management routines. Organizations should implement immediate patch deployment across all affected Windows 10 systems, particularly those running WSL components. Additional defensive measures include disabling WSL functionality for users who do not require Linux environment access, implementing strict network segmentation to limit potential attack vectors, and monitoring for anomalous WSL process behavior that might indicate exploitation attempts. Security professionals should also consider implementing runtime protection mechanisms that can detect and prevent memory corruption patterns associated with this vulnerability. The fix addresses the underlying integer overflow by implementing proper bounds checking and input validation within the WSL subsystem's memory management functions, ensuring that integer values remain within acceptable ranges during memory allocation operations. This vulnerability aligns with CWE-190, which describes integer overflow conditions, and represents a classic example of how improper input validation in kernel-level components can lead to privilege escalation. From an ATT&CK perspective, this vulnerability maps to privilege escalation techniques involving kernel exploits and memory corruption, demonstrating the critical importance of maintaining secure kernel interfaces in operating system design. Organizations should also consider implementing principle of least privilege controls to minimize the potential impact of successful exploitation attempts.