CVE-2014-10072 in zsh
Summary
by MITRE
In utils.c in zsh before 5.0.6, there is a buffer overflow when scanning very long directory paths for symbolic links.
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Analysis
by VulDB Data Team • 02/16/2023
The vulnerability identified as CVE-2014-10072 represents a critical buffer overflow condition within the zsh shell utility version 5.0.5 and earlier. This flaw exists in the utils.c source file where the shell processes directory paths during symbolic link scanning operations. The issue manifests when zsh encounters extremely long directory paths that exceed the allocated buffer size, leading to potential memory corruption and arbitrary code execution. The vulnerability stems from insufficient input validation and boundary checking during path processing, creating an environment where attacker-controlled input can overflow predetermined memory buffers.
The technical implementation of this vulnerability involves the shell's handling of directory traversal operations where it attempts to scan symbolic links within deeply nested or excessively long path structures. When zsh processes such paths, it fails to properly validate the length of directory components against the allocated buffer space, typically resulting in a classic stack-based buffer overflow. This condition allows malicious actors to overwrite adjacent memory locations, potentially corrupting program execution flow and enabling privilege escalation attacks. The vulnerability operates at the system call level where file system operations intersect with shell parsing logic, making it particularly dangerous in environments where zsh is used for automated processes or user interaction.
The operational impact of CVE-2014-10072 extends beyond simple denial of service conditions to encompass full system compromise potential. An attacker with the ability to manipulate directory paths or trigger zsh execution with crafted inputs could leverage this vulnerability to execute arbitrary code with the privileges of the executing user. This makes the vulnerability particularly concerning in multi-user environments or when zsh is used in security-sensitive contexts such as automated deployment scripts, system administration tasks, or web server configurations that invoke shell commands. The vulnerability aligns with CWE-121, which describes stack-based buffer overflow conditions, and may map to ATT&CK technique T1059.004 for shell command execution and T1068 for privilege escalation through local exploits.
Mitigation strategies for this vulnerability require immediate patching of zsh installations to version 5.0.6 or later where the buffer overflow has been addressed through proper input validation and buffer size management. System administrators should also implement monitoring for unusual directory path patterns or shell execution patterns that might indicate exploitation attempts. Additional defensive measures include restricting shell access for untrusted users, implementing proper input sanitization in applications that invoke zsh, and conducting regular security assessments of shell environments. The vulnerability demonstrates the importance of proper memory management and input validation in shell utilities, highlighting how seemingly benign operations like directory path scanning can become attack vectors when proper bounds checking is absent. Organizations should prioritize updating their zsh installations and implementing comprehensive security monitoring to prevent exploitation of this and similar buffer overflow vulnerabilities in their environments.