CVE-2001-1113 in Trollftpd
Summary
by MITRE
Buffer overflow in TrollFTPD 1.26 and earlier allows local users to execute arbitrary code by creating a series of deeply nested directories with long names, then running the ls -R (recursive) command.
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Analysis
by VulDB Data Team • 09/29/2025
The vulnerability identified as CVE-2001-1113 represents a classic buffer overflow flaw within the TrollFTPD file transfer protocol server implementation. This security weakness affects versions 1.26 and earlier, specifically targeting the directory listing functionality when processing recursive directory structures. The flaw manifests when local users exploit the system by creating deeply nested directory hierarchies with excessively long directory names, ultimately triggering the buffer overflow condition during execution of the ls -R command. This type of vulnerability falls under the CWE-121 category of stack-based buffer overflow, where insufficient bounds checking allows attackers to overwrite adjacent memory locations.
The technical implementation of this vulnerability exploits the lack of proper input validation within the directory traversal and listing mechanisms of the TrollFTPD server. When the ls -R command processes deeply nested directories with long names, the system fails to properly validate the length of directory paths before attempting to store them in fixed-size buffers. This allows attackers to exceed the allocated buffer space and overwrite critical memory segments including return addresses and stack pointers. The vulnerability specifically impacts the recursive directory listing functionality, where the command processes directory structures in a depth-first manner, amplifying the buffer overflow effect through the cumulative effect of multiple nested directory names.
The operational impact of this vulnerability extends beyond simple local privilege escalation to potentially enable complete system compromise. Local users who can create files and directories can leverage this flaw to execute arbitrary code with the privileges of the running FTP daemon process. This creates a significant security risk as the compromised service typically operates with elevated permissions to manage file systems and network connections. The attack vector requires local system access but does not necessitate network connectivity, making it particularly dangerous in environments where local users have access to system resources. From an attack framework perspective, this vulnerability aligns with ATT&CK technique T1068 for local privilege escalation and T1548.001 for abuse of system permissions.
Mitigation strategies for this vulnerability require immediate patching of the TrollFTPD software to versions that properly implement bounds checking for directory names and recursive listing operations. System administrators should implement strict directory naming policies that limit the depth and length of directory names to prevent exploitation. Additionally, the principle of least privilege should be enforced by running FTP services with minimal required permissions and implementing proper input validation at all system interfaces. Network segmentation and monitoring solutions should be deployed to detect unusual directory creation patterns that might indicate attempted exploitation. The vulnerability demonstrates the critical importance of input validation and buffer management in server applications, particularly those handling user-provided data through file system operations. Organizations should also consider implementing automated vulnerability scanning tools to identify similar buffer overflow conditions in other legacy software components that may be running on their systems.