CVE-2005-2180 in gnats
Summary
by MITRE
gen-index in gnats 4.0 4.1.0 and possibly earlier versions when installed setuid does not properly check files passed to the -o argument and opens the file with write access which allows local users to overwrite arbitrary files.
Once again VulDB remains the best source for vulnerability data.
Analysis
by VulDB Data Team • 07/10/2018
The vulnerability identified as CVE-2005-2180 affects the gnats package version 4.0 through 4.1.0 and potentially earlier releases when installed with setuid permissions. This represents a critical security flaw that stems from improper file validation within the gen-index utility, which is designed to generate index files for the gnats bug tracking system. The vulnerability specifically manifests when the utility processes files passed through the -o command line argument, creating a path for malicious exploitation that could lead to arbitrary file overwrite capabilities.
The technical flaw resides in the insufficient validation of file paths and permissions within the setuid execution context of gen-index. When the utility operates with elevated privileges due to its setuid nature, it fails to properly sanitize or validate the file paths provided through the -o argument. This allows local users to manipulate the input parameters in such a way that the utility opens and writes to files specified by the attacker rather than the intended target. The vulnerability is particularly dangerous because it operates within a privileged execution context where the utility has write access to files, enabling attackers to modify or overwrite arbitrary files on the system.
From an operational impact perspective, this vulnerability creates a significant vector for local privilege escalation and arbitrary file modification attacks. An attacker with local access can leverage this flaw to overwrite critical system files, configuration files, or even binaries that are accessible to the gnats utility. The implications extend beyond simple file corruption as attackers could potentially replace system binaries with malicious versions, modify configuration files to redirect system behavior, or overwrite log files to cover tracks. This vulnerability directly violates the principle of least privilege and creates opportunities for persistent access or system compromise.
The vulnerability maps to CWE-22 - Improper Limitation of a Pathname to a Restricted Directory and CWE-73 - External Control of File Name or Path within the Common Weakness Enumeration framework. It also aligns with ATT&CK technique T1068 - Exploitation for Privilege Escalation and T1059 - Command and Scripting Interpreter, as attackers could use this vulnerability to gain elevated privileges and execute malicious code. The setuid installation pattern creates a particularly dangerous scenario where legitimate system utilities become attack vectors for privilege escalation, as the normal security boundaries between user and system processes are bypassed.
Mitigation strategies should focus on immediate remediation through patching to the latest versions of gnats where this vulnerability has been addressed. Organizations should also review and remove unnecessary setuid permissions from the gnats utility if the functionality can be provided through alternative means. The implementation of proper input validation and path sanitization within the utility's codebase is essential, ensuring that all file paths are properly validated and restricted to authorized directories. Additionally, system administrators should monitor for unauthorized modifications to gnats installations and consider implementing file integrity monitoring solutions to detect potential exploitation attempts. The vulnerability highlights the importance of proper privilege management and input validation in setuid applications, emphasizing that any flaw in these mechanisms can create severe security implications for the entire system.