How the CVE Works:
The vulnerability in `parse-git-config` v3.0.0 arises due to improper handling of user-supplied input in the `expandKeys` function. Prototype pollution occurs when an attacker manipulates the `__proto__` property of an object, injecting malicious properties into the prototype chain. This can lead to sensitive information disclosure, denial of service, or remote code execution. In this case, the `expandKeys` function fails to sanitize input, allowing an attacker to pollute the prototype of objects used within the application. This can be exploited by crafting a malicious `.gitconfig` file, which, when parsed, triggers the pollution and compromises the application.
DailyCVE Form:
Platform: Node.js
Version: 3.0.0
Vulnerability: Prototype Pollution
Severity: High
Date: Mar 12, 2025
What Undercode Say:
Exploitation:
1. Crafting Malicious Input:
Create a `.gitconfig` file with malicious payloads targeting the `__proto__` property.
Example:
[bash] <strong>proto</strong>.polluted = "true"
2. Triggering the Vulnerability:
Use the `parse-git-config` library to parse the malicious file.
Example:
const parseGitConfig = require('parse-git-config');
const config = parseGitConfig.sync({ path: 'malicious.gitconfig' });
3. Exploiting the Pollution:
The polluted prototype can now be used to manipulate application behavior or leak sensitive data.
Protection:
1. Input Sanitization:
Validate and sanitize all user inputs to prevent prototype pollution.
Example:
function sanitizeInput(obj) {
if (obj.hasOwnProperty('<strong>proto</strong>')) {
throw new Error('Invalid input');
}
return obj;
}
2. Library Update:
Upgrade to a patched version of `parse-git-config` if available.
3. Use Safe Alternatives:
Replace `parse-git-config` with libraries that are not vulnerable to prototype pollution.
4. Freeze Prototypes:
Use `Object.freeze` to prevent modifications to the prototype.
Example:
Object.freeze(Object.prototype);
5. Monitoring and Logging:
Implement monitoring to detect unusual behavior or attempts to exploit the vulnerability.
Commands:
- Check for Vulnerable Versions:
npm list parse-git-config
- Upgrade Library:
npm install parse-git-config@latest
- Scan for Prototype Pollution:
Use tools like `npm audit` or specialized security scanners.
Code Snippets:
- Detecting Pollution:
if (Object.prototype.polluted) { console.log('Prototype pollution detected!'); } - Preventing Pollution:
const safeParse = (input) => { const obj = JSON.parse(input); if (obj.<strong>proto</strong>) { throw new Error('Malicious input detected'); } return obj; };By following these steps, developers can mitigate the risks associated with this high-severity vulnerability.
References:
Reported By: https://github.com/advisories/GHSA-8g77-54rh-46hx
Extra Source Hub:
Undercode
