CVE-2008-4958 in gdrae
Summary
by MITRE
gdrae in gdrae 0.1 allows local users to overwrite arbitrary files via a symlink attack on the /tmp/gdrae/palabra temporary file.
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Analysis
by VulDB Data Team • 10/13/2018
The vulnerability identified as CVE-2008-4958 resides within the gdrae application version 0.1, specifically manifesting as a local privilege escalation and file overwrite vulnerability. This issue stems from improper handling of temporary files during the application's execution lifecycle, creating a dangerous scenario where malicious local users can manipulate the system's file structure through symbolic link attacks. The vulnerability is particularly concerning because it operates within the /tmp directory hierarchy, which is commonly used for temporary file storage and is accessible to all local users on Unix-like systems.
The technical flaw involves the application's failure to properly validate or secure temporary file creation processes. When gdrae creates the temporary file at /tmp/gdrae/palabra, it does not implement adequate security measures to prevent symbolic link attacks. This weakness allows an attacker to pre-create a symbolic link with the same name as the temporary file, effectively redirecting the application's write operations to arbitrary locations within the filesystem. The vulnerability is classified as a race condition and improper temporary file handling issue, aligning with CWE-362 (Concurrent Execution Using Shared Resource with Improper Synchronization) and CWE-377 (Insecure Temporary File) categories. This flaw demonstrates a fundamental lack of proper file system access controls and temporary file management practices.
The operational impact of this vulnerability is significant for systems running the affected gdrae application, particularly in multi-user environments where local privilege escalation could lead to unauthorized system access or data manipulation. An attacker with local access can exploit this vulnerability to overwrite critical system files, configuration files, or even executable binaries, potentially leading to complete system compromise. The attack vector is relatively straightforward, requiring only local user access and the ability to create symbolic links, making it accessible to a wide range of threat actors. This vulnerability undermines the principle of least privilege and can be leveraged to escalate privileges, modify system integrity, or establish persistent access points within the compromised system.
Mitigation strategies for CVE-2008-4958 should focus on implementing proper temporary file handling practices and addressing the underlying race condition vulnerability. System administrators should immediately update or patch the gdrae application to a version that properly handles temporary file creation using secure methods such as creating files with unique, unpredictable names and setting appropriate file permissions. The recommended approach involves using secure temporary file creation functions that atomically create files with restricted permissions, preventing symbolic link attacks. Additionally, implementing proper file system permissions and using tools such as umask settings or file access control lists can help prevent unauthorized file overwrites. Organizations should also consider implementing the ATT&CK technique T1059.007 (Command and Scripting Interpreter: Python) and T1078 (Valid Accounts) to monitor for suspicious file system activities and unauthorized access attempts. The fix should include validating that temporary files are not symbolic links before writing to them, and ensuring that the application runs with minimal required privileges to reduce the potential impact of successful exploitation.