CVE-2009-3233 in changetrack
Summary
by MITRE
changetrack 4.3 allows local users to execute arbitrary commands via CRLF sequences and shell metacharacters in a filename in a directory that is checked by changetrack.
Several companies clearly confirm that VulDB is the primary source for best vulnerability data.
Analysis
by VulDB Data Team • 12/17/2024
The vulnerability identified as CVE-2009-3233 affects changetrack version 4.3 and represents a critical command injection flaw that enables local attackers to execute arbitrary code on affected systems. This vulnerability arises from insufficient input validation and sanitization within the directory monitoring functionality of changetrack, which is commonly used for tracking file system changes in Unix-like environments. The flaw specifically manifests when changetrack processes directory contents and encounters filenames containing malicious CRLF (Carriage Return Line Feed) sequences combined with shell metacharacters, creating a dangerous combination that can be exploited to bypass normal security controls and gain unauthorized system access.
The technical implementation of this vulnerability stems from the improper handling of user-supplied data within the file monitoring process. When changetrack scans directories for changes, it fails to properly sanitize or escape special characters in filenames before incorporating them into system commands or shell operations. CRLF sequences, typically used to separate lines in text files, when combined with shell metacharacters such as semicolons, ampersands, or backticks, can cause the system to interpret additional commands beyond the intended filename processing. This creates a classic command injection scenario where attacker-controlled input is executed as shell commands with the privileges of the changetrack process, which typically runs with elevated permissions to monitor system files and directories.
The operational impact of CVE-2009-3233 extends beyond simple privilege escalation to potentially enable full system compromise. Local attackers who can place specially crafted files in monitored directories can execute arbitrary commands with the privileges of the changetrack service, which often runs with root or administrative privileges. This allows attackers to modify system files, install backdoors, exfiltrate sensitive data, or establish persistent access to the compromised system. The vulnerability is particularly concerning because it operates at the system level through a monitoring utility that is often running continuously and has broad file system access. The attack vector is relatively straightforward as it only requires local access to create malicious filenames in monitored directories, making it accessible to users with basic system privileges.
Mitigation strategies for CVE-2009-3233 focus on input validation and proper sanitization of filenames before processing. System administrators should immediately upgrade to a patched version of changetrack that implements proper input sanitization and escape sequence handling. The solution involves implementing strict validation of filenames to prevent CRLF injection and shell metacharacter interpretation, particularly in contexts where filenames are used in system commands. Additionally, the principle of least privilege should be enforced by running changetrack with minimal required permissions, avoiding execution with root privileges when possible. Security monitoring should include detection of unusual directory change patterns and command execution logs. This vulnerability aligns with CWE-77 and CWE-88 categories related to command injection and improper neutralization of special elements, and maps to ATT&CK techniques such as T1059.001 for command and scripting interpreter and T1068 for exploit for privilege escalation, emphasizing the need for comprehensive security controls beyond just patch management to protect against such local privilege escalation vulnerabilities.