CVE-2003-0847 in Linux
Summary
by MITRE
SuSEconfig.susewm in the susewm package on SuSE Linux 8.2Pro allows local users to overwrite arbitrary files via a symlink attack on the susewm.$$ temporary file.
If you want to get best quality of vulnerability data, you may have to visit VulDB.
Analysis
by VulDB Data Team • 11/24/2024
The vulnerability described in CVE-2003-0847 represents a classic file system race condition and symlink attack scenario that affects the susewm package distributed with SuSE Linux 8.2 Professional. This issue specifically targets the SuSEconfig.susewm script which is responsible for configuring the window manager settings during system initialization or updates. The flaw exists in how the script handles temporary file creation and management, creating a window of opportunity for local attackers to manipulate the system's configuration process through symbolic link manipulation.
The technical implementation of this vulnerability stems from the insecure handling of temporary files within the SuSEconfig.susewm script. When the script executes, it creates a temporary file named susewm.$$ where the $$ represents the process ID of the running script. This temporary file creation pattern is inherently problematic because it exposes the system to race condition attacks. Local users can exploit this by creating symbolic links with the same name as the temporary file before the script attempts to create it, effectively redirecting the script's file operations to arbitrary locations on the filesystem. This type of vulnerability maps directly to CWE-367 which specifically addresses Time-of-Check to Time-of-Use (TOCTOU) race conditions, and also relates to CWE-22 which covers path traversal and directory traversal issues.
The operational impact of this vulnerability is significant for systems running SuSE Linux 8.2 Professional, as it allows local attackers with minimal privileges to overwrite arbitrary files on the system. This can lead to privilege escalation scenarios where attackers might overwrite critical system binaries, configuration files, or even create malicious files that will be executed with elevated privileges during normal system operations. The attack vector is particularly concerning because it requires only local access to the system, meaning that any user with login privileges can potentially exploit this vulnerability. The attack typically involves creating a symbolic link in the directory where the temporary file is expected to be created, then waiting for the vulnerable script to execute and perform file operations on the symlinked location.
Mitigation strategies for this vulnerability must address both the immediate security issue and the underlying design flaw in the script's temporary file handling. The most effective immediate solution involves patching the susewm package to implement proper temporary file creation using secure methods such as creating files with unique, unpredictable names and ensuring proper file permissions. System administrators should also implement proper file system permissions and monitoring to detect unauthorized symbolic link creation in critical directories. The remediation process should follow ATT&CK technique T1068 which addresses privilege escalation through local exploitation of system vulnerabilities, requiring administrators to maintain up-to-date system packages and implement proper access controls. Additionally, implementing mandatory access controls and regular security audits can help detect and prevent similar vulnerabilities from being exploited in other system components. Organizations should also consider implementing file integrity monitoring solutions to detect unauthorized modifications to critical system files that might result from exploitation of this vulnerability.