Server-Side Request Forgery (SSRF) is one of those bugs that seems small but can have a huge impact. In this long read, we’ll break down CVE-2022-40296 — an SSRF vulnerability that let attackers turn a routine web app into a powerful tool for probing internal networks, leaking sensitive data, and launching attacks on other systems.

What is Server-Side Request Forgery (SSRF)?

SSRF happens when a web application fetches resources from user-supplied URLs or addresses, but fails to properly filter or validate them. If you give it a link, it goes and gets it — even if it shouldn’t.

That means an attacker can trick the backend into sending requests to places only it can access, like local resources, private APIs, metadata services (like for cloud providers), or other protected endpoints. Sometimes, these requests leak back responses, open the door to more bugs, or even allow lateral movement in the network.

Where Did CVE-2022-40296 Appear?

CVE-2022-40296 hit Aerospike Management Console (AMC), a web interface for managing Aerospike databases. The management console accepted external URLs from users — but didn’t restrict internal endpoints.

Security Advisory:  
- Official Aerospike advisory: https://community.aerospike.com/t/amc-server-side-request-forgery-ssrf-vulnerability-cve-2022-40296/13080  
- NVD Details: https://nvd.nist.gov/vuln/detail/CVE-2022-40296

How Did the SSRF Work? (With Example Code)

### The Vulnerable Code (Actual commit diff here)

The problem happened in a route that accepted a URL to fetch

// Vulnerable Express.js endpoint (simplified for illustration)
app.post('/fetchUrl', function(req, res) {
  const userUrl = req.body.url;
  fetch(userUrl)
    .then(response => response.text())
    .then(data => res.send(data))
    .catch(err => res.status(500).send("Error!"));
});

What’s missing?
*No filtering of user input. The code trusts that the URL is safe.*

`http

POST /fetchUrl HTTP/1.1

Host: victim.com

Content-Type: application/json

  {
    "url": "http://localhost:800/private-api"
  }

Dump data from internal-only endpoints

- Reach restricted cloud services (http://169.254.169.254/latest/meta-data/ for AWS)

Example: Dumping AWS Metadata

{
  "url": "http://169.254.169.254/latest/meta-data/iam/security-credentials/"
}

If the backend runs on AWS, this can leak application credentials for the instance — a real cloud security disaster.

An attacker cycles through ports like

{ "url": "http://127...1:808/health"; }
{ "url": "http://10...5:3306/"; }

1. Always validate and whitelist allowed URLs

const allowedDomains = ['https://trusted-external.com';];
const inputUrl = new URL(userUrl);

if (!allowedDomains.includes(inputUrl.origin)) {
    return res.status(403).send('Forbidden URL');
}

2. Block internal IP subnets

You can add a check to block requests to private IP spaces like 127...1, 10.../8, 169.254../16, etc.

3. Use outgoing firewall rules

Don’t let your application server make arbitrary outbound connections.

Why This Matters

SSRF is behind many modern high-impact breaches (see the Capital One hack, for example). CVE-2022-40296 in Aerospike Management Console is another clear reminder:

References & Further Reading

- Aerospike Official Advisory
- GitHub Patch Commit
- CVE Details
- SSRF Explained (Imperva)
- PortSwigger SSRF Labs

Takeaway

CVE-2022-40296 shows that with just a tiny missing filter, an attacker can weaponize your backend as a hacking launchpad. Always validate, always restrict, and understand that anything your server can reach, so can attackers — unless you block it!


*Stay safe — fix SSRF before it ruins your day!*

Timeline

Published on: 10/31/2022 21:15:00 UTC
Last modified on: 11/03/2022 02:46:00 UTC