CVE-2018-0596 in Visual Studio Community
Summary
by MITRE
Untrusted search path vulnerability in the installer of Visual Studio Community allows an attacker to gain privileges via a Trojan horse DLL in an unspecified directory.
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Analysis
by VulDB Data Team • 02/22/2020
The vulnerability identified as CVE-2018-0596 represents a critical untrusted search path issue within the Visual Studio Community installer component. This flaw stems from the installer's improper handling of dynamic link library loading mechanisms, where the system searches for required libraries in a predictable but insecure sequence of directories. The vulnerability specifically affects the installation process of Visual Studio Community, creating a pathway for malicious actors to execute arbitrary code with elevated privileges. The issue manifests when the installer encounters a Trojan horse DLL file placed in a directory that is searched before the legitimate system directories, allowing attackers to inject malicious code that executes with the privileges of the installer process.
From a technical perspective, this vulnerability aligns with CWE-427 Uncontrolled Search Path Element, which describes how applications that search for files in a list of directories without proper validation can be exploited by placing malicious files in earlier directories. The installer's search path behavior creates an environment where attackers can manipulate the loading sequence by placing malicious DLLs in directories such as the current working directory, user-writable locations, or other paths that are prioritized in the search order. This particular flaw is classified under the ATT&CK technique T1059.001 Command and Scripting Interpreter, as it enables adversaries to execute malicious code through legitimate system processes, and T1068 Exploitation for Privilege Escalation, since the installer typically runs with elevated permissions. The vulnerability demonstrates how installer components often inherit elevated privileges and can become attractive targets for privilege escalation attacks.
The operational impact of CVE-2018-0596 extends beyond simple code execution, as it can lead to complete system compromise when attackers leverage the elevated privileges of the installer process. An attacker who successfully places a malicious DLL in the appropriate location can gain the same privileges as the installer, potentially enabling them to modify system files, install backdoors, or establish persistent access. This vulnerability is particularly concerning because Visual Studio Community is widely distributed and used by developers, making it an attractive target for attackers seeking to exploit the software installation process. The attack vector requires minimal user interaction beyond running the installer, as the malicious DLL placement can occur through various means including phishing, supply chain attacks, or compromised update mechanisms. Organizations using Visual Studio Community are at risk of privilege escalation attacks that could result in complete system compromise, especially when developers with administrative privileges run the installer.
Mitigation strategies for CVE-2018-0596 should focus on both immediate remediation and long-term architectural improvements. The most effective immediate solution involves applying the official Microsoft security update that addresses the specific search path vulnerability in the Visual Studio installer. Organizations should also implement strict access controls on installation directories, ensuring that only authorized personnel can write to locations where installer components execute. System administrators should employ security tools that monitor for suspicious DLL loading patterns and implement application whitelisting policies to prevent execution of unauthorized binaries. The remediation process should include verifying that the Visual Studio installation directory and all related temporary locations are properly secured and that no user-writable directories are included in the default search paths. Additionally, implementing security awareness training for developers can help prevent accidental exploitation through social engineering attacks that might place malicious DLLs in targeted locations, while regular security audits should verify that the installation environment remains secure against similar vulnerabilities in other software components.