CVE-2021-28469
📋 TL;DR
This vulnerability in Visual Studio Code allows remote code execution when a user opens a maliciously crafted file or project. It affects users who open untrusted files in Visual Studio Code, potentially allowing attackers to execute arbitrary code on the victim's system.
💻 Affected Systems
- Visual Studio Code
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise with attacker gaining full control over the victim's machine, potentially leading to data theft, ransomware deployment, or lateral movement within the network.
Likely Case
Local privilege escalation or arbitrary code execution within the context of the Visual Studio Code user, allowing file system access, credential theft, and installation of persistent malware.
If Mitigated
Limited impact if users only open trusted files and proper endpoint security controls are in place to detect malicious activity.
🎯 Exploit Status
Exploitation requires user interaction to open a malicious file. Proof-of-concept code has been published, making exploitation relatively straightforward for attackers.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 1.56.0 and later
Vendor Advisory: https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-28469
Restart Required: Yes
Instructions:
1. Open Visual Studio Code. 2. Click on Help menu. 3. Select Check for Updates. 4. Install update to version 1.56.0 or later. 5. Restart Visual Studio Code after installation.
🔧 Temporary Workarounds
Disable automatic file opening
allConfigure Visual Studio Code to not automatically open files from unknown sources
Set "files.autoSave": "off" in settings.json
Set "workbench.editor.enablePreview": false in settings.json
Restrict file types
allConfigure file associations to open potentially dangerous files in safer applications
Configure system file associations for .json, .js, .ts files to open in text editor instead of VS Code
🧯 If You Can't Patch
- Implement application whitelisting to prevent execution of unauthorized code
- Use endpoint detection and response (EDR) solutions to monitor for suspicious Visual Studio Code activity
🔍 How to Verify
Check if Vulnerable:
Check Visual Studio Code version: Open VS Code, go to Help > About. If version is below 1.56.0, you are vulnerable.Check Version:
code --version (on command line) or check Help > About in GUIVerify Fix Applied:
Verify version is 1.56.0 or higher in Help > About menu.📡 Detection & Monitoring
Log Indicators:
- Unusual Visual Studio Code process spawning child processes
- Visual Studio Code accessing unexpected files or network resources
- Error logs related to file parsing failures
Network Indicators:
- Visual Studio Code making unexpected outbound connections
- Downloads of suspicious files followed by Visual Studio Code execution
SIEM Query:
process_name:"Code.exe" AND (process_child_count > 5 OR network_connection_count > 10)