CVE-2001-0105 in HP-UX
Summary
by MITRE
Vulnerability in top in HP-UX 11.04 and earlier allows local users to overwrite files owned by the "sys" group.
Be aware that VulDB is the high quality source for vulnerability data.
Analysis
by VulDB Data Team • 08/27/2019
The vulnerability identified as CVE-2001-0105 represents a significant privilege escalation flaw within the HP-UX operating system family, specifically affecting versions 11.04 and earlier. This issue resides within the top command execution environment, which is a critical system utility used for monitoring and displaying process information. The vulnerability manifests through improper file permissions and access control mechanisms that allow local users to manipulate files that should be restricted to system administrators or specific privileged groups. The top command in HP-UX traditionally requires elevated privileges to access certain system resources and process information, yet this flaw creates a pathway for unauthorized file manipulation.
The technical root cause of this vulnerability stems from inadequate privilege separation and file access controls within the top command implementation. When the top utility executes, it fails to properly validate the ownership and permissions of files it interacts with, particularly those belonging to the sys group which typically contains system-critical files. This weakness enables local attackers to exploit the command's execution context to overwrite or modify files that are normally protected by the system's group-based access control mechanisms. The vulnerability specifically targets the file system permissions model where files owned by the sys group should be accessible only to users with appropriate system privileges, but the flawed implementation allows arbitrary local users to bypass these protections.
From an operational impact perspective, this vulnerability creates a serious security risk for HP-UX systems running affected versions, as it provides local users with the ability to compromise system integrity through file overwrite operations. Attackers could potentially modify critical system files, configuration data, or log files that belong to the sys group, leading to system instability, data corruption, or even complete system compromise. The vulnerability essentially undermines the fundamental security principle of least privilege by allowing unauthorized file modification, which could enable attackers to establish persistent access or hide malicious activities within the system. The impact extends beyond simple file corruption as it represents a potential vector for privilege escalation attacks that could ultimately allow attackers to gain administrative control over affected systems.
The flaw aligns with CWE-276, which specifically addresses improper file permissions and access control issues within operating systems, and demonstrates characteristics consistent with the ATT&CK technique T1068, which involves privilege escalation through local exploitation. Organizations running HP-UX 11.04 and earlier versions face significant risk of unauthorized file modification attacks that could compromise system security. The vulnerability represents a classic example of how system utilities can introduce security weaknesses when proper access control validation is omitted during development. The attack vector is particularly concerning because it requires only local system access, making it accessible to users who may not have administrative privileges but can still exploit the flaw to modify protected system files. This vulnerability underscores the critical importance of proper privilege management and access control validation in system utilities, particularly those that may be executed with elevated privileges or interact with sensitive system resources.
The recommended mitigation strategy involves immediate patching of affected HP-UX systems with the vendor-provided security updates that address the file permission validation issues within the top command. System administrators should also implement additional monitoring for unauthorized file modifications and access attempts to sys group files. Disabling unnecessary execution of the top command with elevated privileges, where possible, can reduce the attack surface. Organizations should conduct comprehensive security audits to identify any other system utilities that may exhibit similar privilege escalation vulnerabilities and ensure proper file permission controls are implemented across all system components. Regular security assessments and vulnerability scanning should be performed to identify and remediate similar issues before they can be exploited by malicious actors.