CVE-1999-1391 in NeXTstep
Summary
by MITRE
vulnerability in next 1.0a and 1.0 with publicly accessible printers allows local users to gain privileges via a combination of the npd program and weak directory permissions.
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Analysis
by VulDB Data Team • 06/08/2024
The vulnerability described in CVE-1999-1391 represents a significant privilege escalation issue affecting Next Software's NextStep operating system version 1.0a and 1.0. This flaw specifically targets the npd program, which serves as the NextPrinter Daemon responsible for managing printer operations within the system. The vulnerability arises from the combination of the npd program's design and the weak directory permissions that exist within the NextStep environment, creating a path for local users to escalate their privileges from standard user level to administrative access.
The technical exploitation of this vulnerability occurs through a carefully orchestrated combination of system components and permission misconfigurations. The npd program, which handles printer daemon functionality, contains implementation flaws that allow local users to manipulate its behavior when combined with directory permissions that are inadequately restricted. This weakness falls under the category of privilege escalation vulnerabilities where a local attacker can leverage existing system services to gain elevated privileges. The vulnerability is classified as a local privilege escalation issue, with the specific mechanism involving the manipulation of printer daemon processes through weak directory permissions that should normally restrict access to system-critical components.
From an operational perspective, this vulnerability presents a substantial risk to NextStep systems as it allows any local user to potentially gain root-level access to the system. The impact extends beyond simple privilege escalation since it provides attackers with complete control over the affected system, enabling them to modify system files, install malicious software, and access sensitive data. The vulnerability is particularly concerning because it requires minimal privileges to exploit and can be leveraged by any user with access to the system, making it a critical security concern for organizations running NextStep 1.0a or 1.0. The weakness in directory permissions represents a fundamental flaw in the system's security model where proper access controls are not enforced for critical system components.
The mitigation strategies for this vulnerability involve several key approaches that address both the immediate security flaw and the underlying permission structure issues. System administrators should immediately implement proper directory permissions that restrict access to the npd program and related printer daemon components, ensuring that only authorized system processes can modify these critical files. The implementation of proper access control lists and discretionary access controls should be enforced throughout the system to prevent unauthorized modifications. Additionally, the npd program itself should be updated or patched to address the specific implementation flaws that allow privilege escalation. Organizations should also consider implementing mandatory access controls and regular security audits to identify similar permission misconfigurations that could lead to similar vulnerabilities.
This vulnerability aligns with several established security frameworks and threat models, including the Common Weakness Enumeration classification for privilege escalation vulnerabilities and the MITRE ATT&CK framework's privilege escalation tactics. The weakness specifically maps to the technique of "Exploitation for Privilege Escalation" under the ATT&CK framework, where local users exploit system flaws to gain elevated privileges. The vulnerability also relates to CWE-276, which addresses incorrect permissions for critical resources, and CWE-782, which covers exposed services that allow privilege escalation. The security implications of this vulnerability underscore the importance of proper access control implementation and the necessity of maintaining secure directory permissions as fundamental security practices within operating system environments.