CVE-2005-3533 in OSH
Summary
by MITRE
Buffer overflow in OSH before 1.7-15 allows local users to execute arbitrary code via a long current working directory and filename.
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Analysis
by VulDB Data Team • 12/30/2024
The vulnerability described in CVE-2005-3533 represents a classic buffer overflow flaw affecting the OSH shell utility version 1.7-15 and earlier. This issue arises from inadequate input validation within the shell's handling of directory paths and filenames, creating a potential execution path for malicious local users. The vulnerability specifically manifests when the current working directory or filename exceeds predetermined buffer limits, leading to memory corruption that can be exploited to gain unauthorized code execution privileges.
The technical mechanism behind this flaw involves the shell's failure to properly bounds-check string inputs when processing command-line arguments or directory navigation operations. When a local user provides an excessively long current working directory path or filename, the system's buffer allocation becomes insufficient to accommodate the input data. This overflow condition occurs in the shell's internal string handling routines where fixed-size buffers are used without proper validation of input length, resulting in memory overwrite conditions that can be manipulated to redirect program execution flow.
From an operational perspective, this vulnerability poses significant risks to systems running affected versions of OSH, as local users with basic system access can leverage the buffer overflow to execute arbitrary code with the privileges of the shell process. The attack vector requires local system access but does not necessitate network connectivity or specialized network conditions, making it particularly concerning for environments where privilege escalation is a critical security concern. The exploitability of this vulnerability is enhanced by the fact that it can be triggered through normal shell operations without requiring elevated privileges or special attack conditions.
The impact of this vulnerability aligns with CWE-121, which categorizes buffer overflow conditions as a fundamental weakness in software design that can lead to arbitrary code execution. The ATT&CK framework would classify this as a privilege escalation technique, specifically under the category of "Exploitation for Privilege Escalation" where local users can leverage software vulnerabilities to gain elevated system privileges. Organizations should consider implementing immediate mitigations including upgrading to OSH version 1.7-15 or later, which contains the necessary patches to address the buffer overflow conditions.
Security practitioners should implement comprehensive monitoring for unusual shell behavior or command execution patterns that might indicate exploitation attempts. The vulnerability demonstrates the importance of input validation and bounds checking in shell utilities, emphasizing the need for defensive programming practices that prevent memory corruption through proper buffer management. System administrators should prioritize patching this vulnerability as part of routine security maintenance, particularly in environments where multiple local users exist and where the shell utility is frequently used for system operations.