In June 2024, security researchers discovered a new vulnerability in WooCommerce, the incredibly popular WordPress plugin for e-commerce. Tracked as CVE-2024-35777, this flaw highlights how output injection—in simple terms, mixing up data and commands in a web app—can let attackers spoof content. That means hackers could make the shop display fake information, tricking users and potentially damaging a brand’s reputation.
Let’s break down what happened, how it works, and how you can protect your online store.
The bug is officially called
> Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection') vulnerability in Automattic WooCommerce allows Content Spoofing.
This flaw affects all versions of WooCommerce up through 8.9.2 (so, every store that hasn’t updated past that). If someone can send specially crafted data to the store, WooCommerce might not handle it safely. As a result, the attacker can “inject” unexpected content—like fake messages, shopping cart totals, or even fake checkout offers.
How Does the Exploit Work?
At its heart, the vulnerability is a classic injection problem. When an application shows data that came (even partly) from a user, it must make sure that no “special characters” in that data get interpreted as something more than just text. If not, attackers can sneak in content that the app will show as real, trusted messages.
In WooCommerce, this improper handling happens (at least in part) when displaying certain user-controlled fields—like product names, review text, or customer input.
A Simple Exploit Example
Suppose there’s a comment field on a product review, and this field isn’t cleaned up properly. An attacker can submit the following review:
<h2>50% Off All Items!</h2>
<p>Use code: <strong>FAKEDEAL</strong> at checkout.</p>
<!--
If WooCommerce displays this straight onto your shop page, visitors might see an official-looking offer—totally made up by the attacker. The attacker could also use hidden HTML or scripts to manipulate the look of the shop.
#### Real-World Code Snippet: PHP/HTML
Suppose WooCommerce uses this kind of code in a template
<!-- Vulnerable code -->
echo "<div class='review-text'>" . $_POST['review'] . "</div>";
If $_POST['review'] contains malicious HTML, it will appear as real site content.
The correct way would be
// Secure code: escape HTML
echo "<div class='review-text'>" . htmlspecialchars($_POST['review'], ENT_QUOTES, 'UTF-8') . "</div>";
Here, htmlspecialchars() converts < to <, so the browser shows text, not a real heading!
Am I Affected?
If your WooCommerce version is 8.9.2 or lower, you are at risk. WooCommerce runs on over 5 million sites, so lots of stores could be vulnerable.
You can check your plugin version from your WordPress dashboard, under Plugins > WooCommerce.
How to Fix It
1. Update Immediately: Automattic has fixed this issue in new releases. Upgrade to at least WooCommerce 8.9.3 or later.
2. Sanitize Inputs: Make sure any user input is escaped before showing on your site (as shown in the safe code example above).
3. Check Your Themes/Plugins: If you’ve got custom code fetching WooCommerce data, sanitize it too!
Resources & References
- Official WooCommerce Site
- NVD CVE-2024-35777 Record
- Wordfence Advisory
- OWASP Injection Cheat Sheet
Conclusion
CVE-2024-35777 is a powerful reminder that output injection is no small issue. If you run WooCommerce, update now. Don’t give attackers the chance to spoof your store’s offers or messages. Clean up your output, and keep your shoppers safe and happy.
Timeline
Published on: 07/09/2024 10:15:03 UTC
Last modified on: 07/09/2024 18:19:14 UTC