CVE-2013-1945 in ruby193
Summary
by MITRE
ruby193 uses an insecure LD_LIBRARY_PATH setting.
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Analysis
by VulDB Data Team • 02/01/2024
The vulnerability described in CVE-2013-1945 pertains to ruby193's insecure handling of the LD_LIBRARY_PATH environment variable, which represents a significant security risk in Unix-like operating systems. This flaw allows attackers to manipulate the dynamic linker's library search path and potentially execute arbitrary code with elevated privileges. The vulnerability stems from ruby193's improper initialization of the LD_LIBRARY_PATH variable during execution, creating opportunities for attackers to inject malicious shared libraries into the ruby interpreter's execution context. This issue directly relates to CWE-426, which addresses the execution of untrusted code through insecure library loading mechanisms, and falls under the broader category of insecure library loading vulnerabilities that have been consistently identified in software security assessments.
The technical exploitation of this vulnerability occurs when ruby193 is executed in an environment where the LD_LIBRARY_PATH variable contains user-controlled paths that are prioritized over system standard library locations. When ruby193 loads shared libraries, it follows the standard dynamic linking procedure where paths specified in LD_LIBRARY_PATH are searched before standard system directories like /lib or /usr/lib. Attackers can leverage this by placing malicious shared libraries in directories that appear earlier in the LD_LIBRARY_PATH, causing ruby193 to load and execute these malicious components instead of legitimate system libraries. This technique aligns with ATT&CK tactic TA0004 (Privilege Escalation) and technique T1068 (Local Privilege Escalation), as successful exploitation can result in elevated privileges for the attacker.
The operational impact of CVE-2013-1945 extends beyond simple code execution to encompass potential system compromise and privilege escalation scenarios. When ruby193 is run with elevated privileges or in environments where users have the ability to modify LD_LIBRARY_PATH, the vulnerability becomes particularly dangerous. This is especially true in multi-user systems or environments where ruby applications are executed with root privileges, such as in system administration scripts or web applications. The vulnerability affects systems where ruby193 is compiled with insecure default library path settings, making it a widespread concern across various Unix and Linux distributions that utilize this particular ruby version. The risk is amplified when ruby193 is used in conjunction with other vulnerable applications that also improperly handle environment variables, creating cascading security implications.
Mitigation strategies for CVE-2013-1945 focus on addressing the root cause of the insecure LD_LIBRARY_PATH handling within ruby193. The most effective approach involves modifying the ruby193 installation to explicitly set LD_LIBRARY_PATH to secure, system-standard paths or to clear the variable entirely before executing any library loading operations. System administrators should implement proper environment variable sanitization procedures and avoid using ruby193 in contexts where user-controlled inputs might influence the library loading process. Additionally, the vulnerability can be addressed through proper privilege management where ruby applications are not executed with elevated privileges unless absolutely necessary, following the principle of least privilege as recommended by security frameworks such as NIST SP 800-53. Organizations should also consider updating to newer ruby versions that have addressed this specific library path handling issue, as ruby193 is an older version that may contain additional security vulnerabilities. The implementation of runtime protections such as address space layout randomization and stack canary mechanisms can further reduce the exploitability of this vulnerability, though these measures are secondary to proper library path handling.