CVE-2020-0604 in Visual Studio Code
Summary
by MITRE
A remote code execution vulnerability exists in Visual Studio Code when it process environment variables after opening a project. An attacker who successfully exploited the vulnerability could run arbitrary code in the context of the current user. If the current user is logged on with administrative user rights, an attacker could take control of the affected system. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights. To exploit this vulnerability, an attacker would need to convince a target to clone a repository and open it in Visual Studio Code. Attacker-specified code would execute when the target opened the integrated terminal. The update address the vulnerability by modifying the way Visual Studio Code handles environment variables.
Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.
Analysis
by VulDB Data Team • 02/23/2026
The vulnerability identified as CVE-2020-0604 represents a critical remote code execution flaw within Microsoft Visual Studio Code that arises during project initialization processes. This security weakness specifically manifests when the development environment processes environment variables following project opening operations, creating an attack vector that adversaries can exploit to gain unauthorized system access. The vulnerability's impact extends beyond simple code execution, as it provides attackers with the capability to assume full user privileges, potentially leading to complete system compromise when targets are running with administrative rights.
The technical mechanism underlying this vulnerability stems from improper handling of environment variables within Visual Studio Code's integrated terminal functionality. When users open projects containing maliciously crafted environment variable configurations, the IDE executes attacker-controlled code within the context of the current user session. This flaw operates through the manipulation of environment variable parsing and execution pathways, allowing malicious actors to inject and execute arbitrary code without requiring direct system-level privileges. The vulnerability specifically affects how Visual Studio Code manages terminal environments and processes user-defined environment variables during project initialization.
From an operational standpoint, this vulnerability presents significant risks to development environments where multiple users collaborate on shared repositories. Attackers can leverage social engineering tactics to convince targets to clone malicious repositories and open them in Visual Studio Code, where the vulnerability automatically triggers upon terminal access. The exploit chain requires minimal user interaction beyond the initial project opening, making it particularly dangerous in enterprise settings where developers frequently work with external code repositories. The attack surface is further expanded by the widespread adoption of Visual Studio Code among development teams, increasing potential impact across various organizational sectors.
The security implications of CVE-2020-0604 align with CWE-78 and CWE-74 standards, which address improper neutralization of special elements used in OS commands and injection flaws respectively. This vulnerability also maps to ATT&CK technique T1059.001, which covers command and scripting interpreter execution, and T1068, which involves exploit for privilege escalation. The remediation implemented by Microsoft addresses the root cause through enhanced environment variable processing mechanisms, specifically modifying how Visual Studio Code validates and sanitizes environment variable inputs before executing terminal commands. This fix ensures that potentially malicious environment variable configurations are properly neutralized during project initialization processes, preventing unauthorized code execution.
Organizations should implement comprehensive mitigation strategies including immediate patch deployment, network monitoring for suspicious repository cloning activities, and user education regarding the risks of opening untrusted repositories in development environments. Additional protective measures include implementing application whitelisting policies, restricting write access to development directories, and establishing secure coding practices for repository management. The vulnerability demonstrates the critical importance of validating all user inputs within development environments, particularly those involving environment variable configurations that can influence system execution paths. Regular security assessments of development tools and continuous monitoring of software update compliance are essential to prevent exploitation of similar vulnerabilities in the broader software development ecosystem.