CVE-2002-1838 in Charities.cron
Summary
by MITRE
Charities.cron 1.0.2 through 1.6.0 allows local users to write to arbitrary files via a symlink attack on temporary files.
If you want to get best quality of vulnerability data, you may have to visit VulDB.
Analysis
by VulDB Data Team • 06/10/2018
The vulnerability identified as CVE-2002-1838 affects charities.cron versions 1.0.2 through 1.6.0 and represents a classic race condition exploit through symbolic link manipulation. This flaw occurs when the application creates temporary files without proper security checks, allowing local attackers to establish malicious symbolic links that can redirect file operations to arbitrary locations on the filesystem. The vulnerability falls under the category of insecure temporary file creation as classified by CWE-377, specifically CWE-378 which addresses the creation of temporary files with insecure permissions and naming practices.
The technical implementation of this vulnerability stems from the application's failure to properly validate or secure temporary file creation processes. When charities.cron generates temporary files, it typically uses predictable naming conventions and creates files in world-writable directories without implementing proper atomic file creation mechanisms. Attackers can exploit this by creating symbolic links with the same names that the application expects to use, effectively hijacking the file creation process. This type of attack is particularly dangerous because it can be executed by any local user with minimal privileges, making it a significant concern for systems where multiple users share the same environment.
The operational impact of this vulnerability extends beyond simple privilege escalation as it can be leveraged to modify critical system files, inject malicious code into the application's execution flow, or even establish persistent backdoors. When successful, attackers can overwrite configuration files, binaries, or system logs with malicious content, potentially compromising the integrity of the entire system. The vulnerability can be exploited through various attack vectors including privilege escalation scenarios where local users can gain elevated privileges, or through direct modification of application data. This attack pattern aligns with ATT&CK technique T1059.007 for command and scripting interpreter and T1548.001 for abuse of sudo privileges.
Mitigation strategies for CVE-2002-1838 should focus on implementing secure temporary file creation practices that prevent symbolic link attacks. The recommended approach involves using atomic file creation methods that ensure files are created with proper permissions and cannot be replaced by symbolic links during the creation process. Organizations should implement proper file access controls, restrict temporary file creation to secure directories with appropriate permissions, and validate all temporary file operations. Additionally, the application should be updated to a patched version that addresses the insecure file handling behavior, as the vulnerability affects multiple versions of the software. System administrators should also consider implementing monitoring and alerting mechanisms to detect suspicious file creation patterns and potential symlink attacks in real-time environments.