CVE-2020-7646
📋 TL;DR
CVE-2020-7646 is a path traversal vulnerability in curlrequest npm package versions through 1.0.1 that allows attackers to read arbitrary files on the server by controlling the 'file' parameter. This affects any application using vulnerable versions of curlrequest to handle user-supplied file paths. The vulnerability enables unauthorized file access without authentication.
💻 Affected Systems
- curlrequest npm package
📦 What is this software?
Curlrequest by Curlrequest Project
⚠️ Risk & Real-World Impact
Worst Case
Complete server compromise through reading sensitive files like /etc/passwd, SSH keys, configuration files, or database credentials, potentially leading to privilege escalation and lateral movement.
Likely Case
Unauthorized access to sensitive application files, configuration data, or user information stored on the filesystem, potentially enabling further attacks.
If Mitigated
Limited impact if proper input validation and file path sanitization are implemented, restricting file access to intended directories only.
🎯 Exploit Status
Exploitation is straightforward - attackers simply need to provide a malicious file path like '../../etc/passwd' to the vulnerable parameter. No special tools or complex techniques required.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 1.0.2
Vendor Advisory: https://github.com/node-js-libs/curlrequest/security/advisories
Restart Required: Yes
Instructions:
1. Update package.json to specify curlrequest version 1.0.2 or higher. 2. Run 'npm update curlrequest' or 'npm install curlrequest@1.0.2'. 3. Restart the Node.js application. 4. Test that file parameter functionality still works correctly.
🔧 Temporary Workarounds
Input Validation and Sanitization
allImplement strict input validation to only allow expected file paths and prevent directory traversal sequences
// Example Node.js validation code:
const path = require('path');
const allowedBase = '/var/www/uploads/';
const userInput = req.body.file;
const resolvedPath = path.resolve(allowedBase, userInput);
if (!resolvedPath.startsWith(allowedBase)) {
throw new Error('Invalid file path');
}
Replace curlrequest with Alternative
allReplace curlrequest with a maintained alternative like node-fetch or axios that doesn't have this vulnerability
npm uninstall curlrequest
npm install node-fetch
🧯 If You Can't Patch
- Implement strict input validation and sanitization for all user-controlled file parameters
- Use application-level file access controls and run the application with minimal file system permissions
🔍 How to Verify
Check if Vulnerable:
Check package.json or run 'npm list curlrequest' to see if version is 1.0.1 or lower. Review code for usage of curlrequest with user-controlled file parameters.Check Version:
npm list curlrequest | grep curlrequestVerify Fix Applied:
After updating, run 'npm list curlrequest' to confirm version 1.0.2 or higher. Test that file access functionality works but path traversal attempts are blocked.📡 Detection & Monitoring
Log Indicators:
- Unusual file access patterns, multiple failed file access attempts, access to system files from application logs
Network Indicators:
- HTTP requests containing path traversal sequences like '../' or '..\' in file parameters
SIEM Query:
source="application.logs" AND ("..\" OR "../" OR "/etc/" OR "/root/") AND "file="