CVE-2003-0875 in OpenSLP
Summary
by MITRE
Symbolic link vulnerability in the slpd script slpd.all_init for OpenSLP before 1.0.11 allows local users to overwrite arbitrary files via the route.check temporary file.
If you want to get best quality of vulnerability data, you may have to visit VulDB.
Analysis
by VulDB Data Team • 06/15/2018
The vulnerability described in CVE-2003-0875 represents a critical symbolic link race condition flaw within the OpenSLP service locator protocol implementation. This issue specifically affects the slpd script known as slpd.all_init which is responsible for initializing the Service Location Protocol daemon. The vulnerability stems from improper handling of temporary files during the service initialization process, creating a window of opportunity for malicious local users to exploit the system.
The technical flaw manifests in the manner in which the slpd.all_init script manages the route.check temporary file. During the initialization sequence, the script creates temporary files without adequate security measures to prevent symbolic link attacks. This race condition vulnerability occurs when the script checks for the existence of a temporary file and subsequently opens it, but an attacker can manipulate the file system between these operations by creating a symbolic link that points to a target file of their choosing. The vulnerability is classified under CWE-377 as "Insecure Temporary File" and specifically aligns with CWE-378 which addresses "Creation of Temporary File With Insecure Permissions."
The operational impact of this vulnerability is significant for systems running OpenSLP versions prior to 1.0.11. A local attacker with minimal privileges can leverage this weakness to overwrite arbitrary files on the system with the privileges of the slpd process. This could result in privilege escalation, data corruption, or even complete system compromise depending on which files are targeted. The attacker could potentially overwrite critical system files, configuration files, or even executable programs, leading to persistent backdoors or system instability. The vulnerability is particularly dangerous because it requires minimal privileges to exploit and can be used to gain elevated access to the system.
The attack vector involves a local user creating a symbolic link to a target file before the slpd.all_init script creates its temporary file, then executing the script which will overwrite the target file with contents from the temporary file. This type of attack is categorized under the ATT&CK technique T1059.001 for Command and Scripting Interpreter and T1068 for Exploitation for Privilege Escalation. The vulnerability demonstrates poor privilege separation and inadequate file system security measures in the service initialization process.
Mitigation strategies for this vulnerability include upgrading to OpenSLP version 1.0.11 or later where the issue has been resolved through proper temporary file handling and security measures. System administrators should also implement proper file permissions and access controls, ensure that temporary files are created with secure permissions, and consider implementing file system monitoring to detect unauthorized symbolic link creation. The fix typically involves ensuring that temporary files are created atomically and with appropriate security attributes to prevent attackers from manipulating the file system during the creation process. Organizations should also conduct regular security audits of service initialization scripts to identify similar race condition vulnerabilities that could be exploited by malicious users.