CVE-2005-0824 in Mathopd
Summary
by MITRE
The internal_dump function in Mathopd before 1.5p5, and 1.6x before 1.6b6 BETA, when Mathopd is running with the -n option, allows local users to overwrite arbitrary files via a symlink attack on dump files that are triggered by a SIGWINCH signal.
Be aware that VulDB is the high quality source for vulnerability data.
Analysis
by VulDB Data Team • 07/22/2017
The vulnerability identified as CVE-2005-0824 affects the mathopd network service daemon, specifically targeting versions prior to 1.5p5 and 1.6x before 1.6b6 BETA. This security flaw resides within the internal_dump function of the application, which handles the dumping of internal state information when the daemon operates with the -n command line option. The issue manifests as a race condition that enables local attackers to exploit a symbolic link attack against dump files, creating a significant privilege escalation vector. The vulnerability becomes exploitable when the mathopd daemon receives a SIGWINCH signal, typically sent when a terminal window is resized, triggering the problematic dump functionality.
The technical implementation of this vulnerability stems from improper handling of temporary files during the dump operation. When mathopd executes with the -n option, it creates dump files in a predictable location without adequate protection against symbolic link manipulation. The internal_dump function does not validate whether the target file path points to a symbolic link before attempting to write data to it. This behavior creates a window of opportunity where a local attacker can establish a symbolic link pointing to a sensitive system file, such as /etc/passwd or another critical configuration file, before the dump operation occurs. The race condition occurs because the file creation and writing operations are not atomic, allowing the attacker to replace the intended target with their own malicious symlink.
The operational impact of this vulnerability extends beyond simple file overwriting, as it provides attackers with a mechanism to modify critical system files with elevated privileges. Since mathopd typically runs with elevated privileges to perform network operations and system management tasks, successful exploitation can lead to unauthorized modification of system configuration files, user account information, or other sensitive data. The vulnerability is particularly concerning because it requires only local user access to exploit, meaning that any user with access to the system can potentially leverage this flaw. This local privilege escalation capability can be used to establish persistent access, modify system integrity, or disable security controls within the affected environment.
Mitigation strategies for CVE-2005-0824 primarily involve upgrading to patched versions of mathopd, specifically versions 1.5p5 or 1.6b6 BETA and later. System administrators should also implement proper file permissions and access controls to minimize the impact of potential exploitation. The vulnerability aligns with CWE-377, which describes insecure temporary file handling, and CWE-367, addressing time-of-check to time-of-use race conditions. From an attack perspective, this vulnerability would be categorized under the ATT&CK technique T1068, which covers privilege escalation through local exploits, and T1548.001, covering abuse of system privileges. Organizations should also consider implementing monitoring for suspicious SIGWINCH signal activity and file system changes in locations where dump files are stored. Additionally, the principle of least privilege should be enforced by ensuring that mathopd runs with minimal required permissions, and the -n option should be avoided when possible to prevent triggering the vulnerable code path.