CVE-2002-0790 in AIX
Summary
by MITRE
clchkspuser and clpasswdremote in AIX expose an encrypted password in the cspoc.log file, which could allow local users to gain privileges.
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Analysis
by VulDB Data Team • 09/04/2019
The vulnerability identified as CVE-2002-0790 affects IBM AIX operating systems and specifically targets two command line utilities named clchkspuser and clpasswdremote. These tools are part of the AIX security framework and are designed to perform user account validation and password management operations within the system. The flaw manifests when these utilities execute and write their operational logs to the cspoc.log file, which contains sensitive authentication information in an encrypted format that can be exploited by local attackers.
The technical implementation of this vulnerability stems from improper handling of sensitive data within the logging mechanisms of these AIX utilities. When clchkspuser and clpasswdremote process user authentication requests, they store encrypted password information in the cspoc.log file without adequate protection measures. This logging behavior violates fundamental security principles regarding the handling of authentication credentials and creates an attack surface that allows local users to access the log file and extract the encrypted password data. The vulnerability represents a classic case of information exposure where sensitive data is stored in a location accessible to unauthorized users.
From an operational impact perspective, this vulnerability enables local privilege escalation attacks by allowing attackers to obtain encrypted password hashes that can potentially be cracked or used in further attacks. The exposure of encrypted passwords in system logs creates a significant risk for systems where local access is possible, as these credentials could be exploited to gain unauthorized access to user accounts or administrative privileges. The vulnerability affects the integrity and confidentiality of the authentication system, potentially compromising the entire security posture of AIX systems that rely on these utilities for account management.
Security practitioners should implement immediate mitigations including restricting file permissions on the cspoc.log file to prevent unauthorized access, disabling or removing the vulnerable utilities if they are not essential for operations, and implementing monitoring for unauthorized access attempts to log files. The vulnerability aligns with CWE-312 (Sensitive Data Exposure) and CWE-200 (Information Exposure) categories, and represents a technique that could be categorized under ATT&CK tactic TA0006 (Credential Access) and technique T1555 (Credentials from Password Stores). Organizations should also consider implementing log file auditing and access controls to prevent unauthorized reading of system log files, as well as applying the appropriate IBM AIX security patches that address this specific vulnerability in the command line utilities.
The broader implications of this vulnerability highlight the importance of secure coding practices and proper access control mechanisms within system utilities. It demonstrates how seemingly routine logging operations can create security weaknesses when sensitive data is not properly protected, emphasizing the need for comprehensive security reviews of all system components and the implementation of defense-in-depth strategies that protect against information disclosure attacks at multiple layers of the system architecture.