CVE-1999-0664 in Windows
Summary
by MITRE
An application-critical Windows NT registry key has inappropriate permissions.
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Analysis
by VulDB Data Team • 04/18/2026
The vulnerability described in CVE-1999-0664 represents a critical access control flaw within the Windows NT operating system registry architecture. This issue specifically targets a registry key that is fundamental to the system's operation, where the permissions assigned to this critical component are inadequately configured, allowing unauthorized access that could compromise system integrity and security posture. The Windows NT registry serves as the central repository for system configuration data, making any misconfiguration of registry permissions particularly dangerous as it can provide attackers with elevated privileges or access to sensitive system information.
The technical flaw stems from improper permission settings on a registry key that is essential for application functionality and system operation. In Windows NT systems, registry keys are protected by access control lists that define which users or groups can read, write, or modify specific registry entries. When these permissions are improperly configured, particularly for critical system keys, malicious actors can exploit this weakness to gain unauthorized access to system resources. This vulnerability falls under the category of privilege escalation, where an attacker can leverage the improperly configured registry key to elevate their privileges beyond what is normally permitted. The issue demonstrates a failure in the principle of least privilege, where system components are granted more access rights than necessary for their operation.
The operational impact of this vulnerability extends beyond simple unauthorized access, as it can enable attackers to modify critical system configurations, install malicious software, or gain elevated privileges that would normally require administrative rights. The registry key in question likely controls essential system functions or application behaviors, meaning that unauthorized modification could lead to system instability, data corruption, or complete system compromise. Attackers could potentially use this vulnerability to establish persistent access, modify security policies, or manipulate system settings to maintain their presence within the compromised environment. This flaw represents a significant threat to system integrity and could affect multiple applications and system services that depend on the proper functioning of this registry key.
Mitigation strategies for CVE-1999-0664 should focus on proper access control configuration and system hardening measures. System administrators must ensure that registry keys are configured with appropriate permissions that follow the principle of least privilege, granting only necessary access rights to specific users or groups. Regular security audits should be conducted to verify that registry permissions are properly configured and that no unauthorized modifications have occurred. The implementation of proper access control lists and regular monitoring of registry access patterns can help detect potential exploitation attempts. Additionally, this vulnerability highlights the importance of following security best practices and maintaining updated system configurations, as many of these registry permission issues were addressed in subsequent Windows NT service packs and security updates. Organizations should also consider implementing security frameworks that align with industry standards such as those recommended by the Center for Internet Security and the National Institute of Standards and Technology to ensure comprehensive system protection. This vulnerability serves as a reminder of the critical importance of proper access control implementation and the potential consequences of inadequate permission settings in operating system components.