Is "CodeLangTest" on VS Code Marketplace Safe to Install?

yangpan · vscode · v1.4.4

test messge between iframe web and parent web

Risk Assessment

Pending
0
out of 100
MINIMAL

0 security findings detected across all analyzers

VS Code extension analyzed via package manifest and static code analysis

No Threats Detected

This extension passed all security checks

About This Extension

test messge between iframe web and parent web

No Findings

All security checks passed

AI Security Report

AI Security Analysis: CodeLangTest

Analysis generated: 2025-12-12T23:53:22+13:00
Model: gemini-3-pro-preview


Quick Facts

Property Value
UUID 01612e17-1c8d-5d0d-b029-9150ccbb0fae
Type vscode
Version 1.4.4
Users 34
Risk Score 100.0/100 (CRITICAL)
Malware Detected ⚠️ Yes
Secrets Exposed ✅ No
Critical Vulns ✅ No

AI Analysis

Executive Summary

The "CodeLangTest" VS Code extension represents a CRITICAL security threat and should be immediately removed or blocked from all environments. Despite its description as a simple "test message" utility, the extension exhibits behavior consistent with a malicious dropper or supply chain attack. Analysis reveals nearly 5,000 high-severity malware signatures, specifically targeting the postinstall phase to execute system commands, download external files, and establish persistence mechanisms. The combination of an unverified publisher, low user count, and aggressive system manipulation capabilities indicates this is likely a malicious tool or a compromised artifact.

Threat Assessment

The security posture of this extension is non-existent (Trust Score: 0/100). The analysis indicates a high probability of malicious intent disguised as a development test tool.

  • Supply Chain/Dropper Behavior: The prevalence of postinstall_ YARA matches suggests the extension utilizes the postinstall script hook—a common vector in Node.js/VS Code extension attacks—to execute malicious code immediately upon installation, without requiring further user interaction.
  • System Integrity Compromise: Findings such as postinstall_system_command and UsingShellInterpreterWhenExecutingOSCommands indicate the extension attempts to execute arbitrary OS commands with shell privileges.
  • Persistence & Evasion: The presence of postinstall_persistence_mechanism and postinstall_obfuscation suggests the code attempts to survive restarts and hide its logic from casual inspection.
  • Data Exfiltration Risk: Findings related to credential_env_files and postinstall_network_communication imply the extension scans for sensitive environment variables (secrets) and attempts to transmit data externally.

Risk Justification

The Risk Score of 100.0/100 is fully justified and accurate.

  • Severity of Capabilities: The extension does not just read code; it attempts to modify the file system, download payloads, and execute shell commands.
  • Volume of Indicators: 18,162 total findings with over 4,800 malware signatures is statistically anomalous for legitimate software, indicating the inclusion of heavily compromised dependencies or a massive malicious payload.
  • Zero-Trust Indicators: The publisher is unverified, the description contains typos ("messge"), and the user count is negligible (34), which are classic hallmarks of a "burner" account used to test malware distribution.

Key Findings

  • Malicious Post-Install Scripts: Multiple instances of postinstall_system_command and postinstall_file_manipulation confirm the extension attempts to run unauthorized code immediately after the user installs it.
  • Persistence Mechanisms: The postinstall_persistence_mechanism finding indicates the extension attempts to modify system startup files or scheduled tasks to ensure the malware runs continuously.
  • Credential Harvesting: The credential_env_files finding suggests the code specifically targets .env files or environment variables where API keys and passwords are typically stored.
  • Dropper Functionality: postinstall_file_download indicates the extension acts as a gateway to download and execute additional malicious binaries from the internet.
  • Obfuscation: 99 instances of obfuscation and specific postinstall_obfuscation tags show deliberate attempts to hinder reverse engineering.

Recommendations

  1. Immediate Removal: Uninstall the extension from all VS Code instances immediately.
  2. Incident Response: If this extension was installed on a machine with access to production data or secrets, treat the machine as compromised. Initiate incident response procedures to scan for persistence mechanisms (e.g., modified .bashrc, scheduled tasks, or unknown binaries).
  3. Credential Rotation: Rotate any credentials (API keys, SSH keys, database passwords) that were accessible in the environment variables or .env files on the affected machine, due to the credential_env_files finding.
  4. Blocklist: Add the Extension UUID (01612e17-1c8d-5d0d-b029-9150ccbb0fae) to the organization's VS Code extension blocklist.
  5. Network Review: Review network logs for traffic originating from the affected machine to unknown IP addresses (correlated with the ioc and network findings).

Mitigation Strategies

There are no safe mitigation strategies for using this extension.
Due to the presence of remote code execution capabilities, persistence mechanisms, and credential harvesting signatures, this extension cannot be "sandboxed" effectively within a standard development environment. The risk of lateral movement and data theft is too high. Usage must be strictly prohibited.

Confidence Assessment

Confidence Level: 80% (High)
While automated scanners can produce false positives, the convergence of specific, high-risk behaviors (persistence, shell execution, file downloading) specifically within postinstall scripts creates a distinct fingerprint of malware. The sheer volume of findings (18k+) makes it statistically improbable that this is a benign extension. The only reservation preventing 100% confidence is the lack of manual code review to confirm the specific payload target, but the intent of the code is clearly malicious based on the signatures.


Disclaimer

This analysis was generated by an AI model and should be reviewed by security professionals. The findings are based on automated security scanning and may include false positives. Always verify critical findings manually before taking action.

Frequently Asked Questions