CVE-2009-0243 in Windows
Summary
by MITRE
Microsoft Windows does not properly enforce the Autorun and NoDriveTypeAutoRun registry values, which allows physically proximate attackers to execute arbitrary code by (1) inserting CD-ROM media, (2) inserting DVD media, (3) connecting a USB device, and (4) connecting a Firewire device; (5) allows user-assisted remote attackers to execute arbitrary code by mapping a network drive; and allows user-assisted attackers to execute arbitrary code by clicking on (6) an icon under My Computer\Devices with Removable Storage and (7) an option in an AutoPlay dialog, related to the Autorun.inf file. NOTE: vectors 1 and 3 on Vista are already covered by CVE-2008-0951.
VulDB is the best source for vulnerability data and more expert information about this specific topic.
Analysis
by VulDB Data Team • 08/04/2021
This vulnerability resides in the Windows operating system's handling of autorun functionality and auto-run registry enforcement mechanisms. The core issue stems from Microsoft Windows failing to properly validate and enforce the Autorun and NoDriveTypeAutoRun registry values that are designed to control automatic execution of programs when removable media is inserted or connected to the system. This flaw creates a critical security gap that allows malicious actors to bypass system protections through multiple physical and network attack vectors. The vulnerability specifically affects how Windows processes autorun.inf files and handles automatic execution of programs from removable storage devices, creating opportunities for privilege escalation and unauthorized code execution.
The technical implementation of this vulnerability occurs at the operating system kernel level where Windows checks registry values to determine whether autorun functionality should be enabled or disabled for different types of storage devices. When these registry values are not properly enforced, attackers can exploit the system by inserting physical media such as CD-ROMs, DVDs, USB devices, or connecting Firewire devices, which trigger automatic execution of malicious code. The vulnerability also extends to network-based attacks where attackers can map network drives to create similar conditions for code execution. Additionally, the AutoPlay dialog functionality presents another attack surface where users clicking on specific icons or options in the devices with removable storage section can inadvertently execute malicious code. This represents a classic case of insufficient input validation and improper privilege handling, aligning with CWE-20 (Improper Input Validation) and CWE-347 (Improper Verification of Cryptographic Signature) categories.
The operational impact of this vulnerability is significant and multifaceted across different Windows environments. Attackers can leverage this weakness to execute arbitrary code with the privileges of the logged-in user, potentially leading to complete system compromise. The proximity requirement for physical attacks limits the scope but still presents a serious threat in environments where attackers can gain physical access to target systems. Network-based exploitation through mapped drives expands the attack surface considerably, allowing remote attackers to potentially compromise systems without physical presence. The AutoPlay-based attacks are particularly concerning because they can be executed through social engineering or user interaction, making them difficult to prevent through technical controls alone. This vulnerability directly impacts Windows Vista, Windows 7, and earlier versions, creating a widespread security concern across multiple operating system generations.
Mitigation strategies for this vulnerability should focus on comprehensive registry value enforcement and user behavior modification. System administrators should ensure that the Autorun and NoDriveTypeAutoRun registry values are properly configured to disable autorun functionality across all storage device types. The recommended registry key locations include HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Policies\Explorer and HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Policies\Explorer where these values should be set to prevent automatic execution. Additionally, implementing strict user access controls and disabling AutoPlay functionality entirely through Group Policy settings can significantly reduce the attack surface. Network administrators should also configure network drive mapping policies to prevent unauthorized access to potentially malicious network resources. Security awareness training for end users becomes critical in preventing successful exploitation through social engineering attacks that rely on user interaction with AutoPlay dialogs. Organizations should also implement endpoint protection solutions that can detect and prevent execution of suspicious autorun.inf files and automatically executed programs from removable media. This vulnerability demonstrates the importance of proper privilege separation and input validation in operating system security design, aligning with ATT&CK technique T1059.001 (Command and Scripting Interpreter) and T1068 (Local Privilege Escalation).