CVE-2012-5380 in Ruby
Summary
by MITRE
Untrusted search path vulnerability in the installation functionality in Ruby 1.9.3-p194, when installed in the top-level C:\ directory, might allow local users to gain privileges via a Trojan horse DLL in the C:\Ruby193\bin directory, which may be added to the PATH system environment variable by an administrator, as demonstrated by a Trojan horse wlbsctrl.dll file used by the "IKE and AuthIP IPsec Keying Modules" system service in Windows Vista SP1, Windows Server 2008 SP2, Windows 7 SP1, and Windows 8 Release Preview. NOTE: CVE disputes this issue because the unsafe PATH is established only by a separate administrative action that is not a default part of the Ruby installation
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Analysis
by VulDB Data Team • 08/13/2025
The vulnerability described in CVE-2012-5380 represents a classic untrusted search path weakness that exploits the trust model inherent in Windows system architecture. This issue specifically affects Ruby 1.9.3-p194 installations when deployed in the root C:\ directory, creating a dangerous scenario where local attackers can manipulate the system's dynamic link library loading mechanism. The vulnerability stems from the installation process placing Ruby binaries in a directory that may be included in the system PATH environment variable through administrative configuration, thereby enabling malicious DLL injection attacks. The technical flaw manifests when the system attempts to resolve dynamic link libraries required by Ruby's installation functionality, particularly in scenarios where the PATH variable includes the C:\Ruby193\bin directory without proper security controls.
The operational impact of this vulnerability extends beyond simple privilege escalation to encompass broader system compromise potential. Attackers can exploit this weakness by placing malicious Trojan horse DLL files in the C:\Ruby193\bin directory, with the wlbsctrl.dll file serving as a demonstrated example that is already loaded by legitimate Windows system services. This creates a persistent threat vector that operates under the guise of legitimate system functionality, as the malicious DLL is loaded by the "IKE and AuthIP IPsec Keying Modules" service, which is a legitimate Windows component. The vulnerability's effectiveness is amplified because the malicious DLL can execute with the privileges of the service that loads it, potentially enabling attackers to perform actions that would otherwise require elevated system access. This particular attack vector demonstrates how seemingly innocuous installation paths can become security risks when combined with administrator configuration practices.
The security implications of CVE-2012-5380 align with CWE-427, which specifically addresses uncontrolled search path vulnerabilities, and can be mapped to ATT&CK technique T1036.005 for masquerading through legitimate system components. The vulnerability's classification as a privilege escalation issue reflects the fundamental security principle that trust relationships within system architectures can be exploited when proper validation mechanisms are absent. The fact that this vulnerability requires a separate administrative action to establish the unsafe PATH configuration means it operates as a secondary attack vector rather than a direct installation flaw, but this distinction does not diminish its potential impact. The vulnerability essentially creates a situation where the Ruby installation process becomes a potential entry point for attackers who can manipulate the system's dynamic loading behavior through carefully placed malicious libraries. This issue highlights the importance of secure installation practices and the need for administrators to carefully consider PATH variable configurations during system setup.
The mitigation strategies for this vulnerability involve multiple layers of defense that address both the installation configuration and the broader system security posture. Administrators should avoid installing Ruby in the root directory structure and instead use dedicated installation paths that do not conflict with system directories. The PATH environment variable should be carefully audited to ensure that Ruby installation directories are not inadvertently included in system-wide PATH configurations without proper security controls. Additionally, system administrators should implement least privilege principles and regularly audit system services to identify potential attack vectors. The vulnerability's disputed nature regarding default installation behavior indicates that proper security awareness and configuration management practices are critical. Organizations should establish secure installation procedures that prevent the inclusion of potentially vulnerable paths in system PATH variables, and implement monitoring solutions that can detect unauthorized DLL loading activities. These measures align with the broader security principle of defense in depth and help prevent similar vulnerabilities from being exploited through path manipulation attacks.