Hey folks! Today, we're going to go deep into CVE-2025-3028. This vulnerability pops up when transforming a document through the XSLTProcessor while also running JavaScript code in some popular browsers like Firefox and Thunderbird.

So as a quick refresher for everyone, the XSLTProcessor is a powerful tool that can be used to transform XML documents into other formats, such as HTML, using XSLT style sheets. The issue here is a use-after-free, which is a type of memory corruption bug that arises when a program continues to use a pointer after it's been freed. This can cause all sorts of undesirable behaviors, and in this case, it can even allow attackers to execute arbitrary code.

Thunderbird < 128.9

Now, let's dig a little deeper into the technical stuff. Suppose we have an XML document and an XSLT stylesheet. A developer may want to transform the XML document using the XSLT stylesheet in the browser with JavaScript. Here's a simple code snippet to demonstrate the concept:

// Load the XML document and XSLT stylesheet
let xmlDoc = new DOMParser().parseFromString(xmlString, 'text/xml');
let xslDoc = new DOMParser().parseFromString(xslString, 'text/xml');

// Use the XSLTProcessor to transform the XML
let xsltProcessor = new XSLTProcessor();
xsltProcessor.importStylesheet(xslDoc);
let resultDoc = xsltProcessor.transformToDocument(xmlDoc);

// Show the transformed result to the user
document.body.appendChild(resultDoc.documentElement);

The problem comes in when the XSLTProcessor is transforming the XML document and JavaScript code is executed. If this execution causes some changes to the underlying XML structure, the XSLTProcessor might still have a reference to the old data, resulting in potential use-after-free vulnerability.

To learn more about the original references and details for this vulnerability, be sure to visit these links:

- CVE-2025-3028 Reference
- Mozilla Security Advisory

So how might an attacker exploit this vulnerability? Well, they could create a malicious website that crafts a specific XML document and XSLT stylesheet combination designed to trigger the bug. They could also use JavaScript on the same page to execute the use-after-free. If a victim visits this malicious site using a vulnerable version of Firefox or Thunderbird, the attacker's code might be executed in the context of the user's browser or email client.

With that said, it's crucial to always keep your software up to date. Make sure your Firefox and Thunderbird are updated to the latest versions to stay protected.

And there you have it, a comprehensive overview of CVE-2025-3028. Do stay vigilant and update your software regularly to prevent security breaches. If you have any questions or concerns, feel free to drop a comment below.

Timeline

Published on: 04/01/2025 13:15:41 UTC
Last modified on: 04/07/2025 13:31:38 UTC