标签：ofo sel frame ima onkeyup show 思路 title 反射
作者：w7ay @知道创宇404实验室为了实现自动刷SRC的目标，过年前就开始对w13scan的xss扫描功能进行优化，灵感来源于xray所宣称的基于语义的扫描技术。
之前xss扫描是参考w3af中的源码，原理也很简单就是暴力的使用xss的payload进行请求，最后在返回文本中查找关键字,xss payload一般有以下几个部分。
后面我认真的学习了一下Xsstrike、Xray、Awvs中的检测技巧以及检测参数，想将它们的优点和为一体。
先说说Xsstrike，里面带有xss扫描和fuzz，但感觉xss扫描的效果也不是太理想。不过它的一些特性还是可以学习的。
Xsstrike的dom扫描，是通过正则来分析敏感函数
sources = r‘‘‘document\.(URL|documentURI|URLUnencoded|baseURI|cookie|referrer)|location\.(href|search|hash|pathname)|window\.name|history\.(pushState|replaceState)(local|session)Storage‘‘‘
sinks = r‘‘‘eval|evaluate|execCommand|assign|navigate|getResponseHeaderopen|showModalDialog|Function|set(Timeout|Interval|Immediate)|execScript|crypto.generateCRMFRequest|ScriptElement\.(src|text|textContent|innerText)|.*?\.onEventName|document\.(write|writeln)|.*?\.innerHTML|Range\.createContextualFragment|(document|window)\.location‘‘‘scripts = re.findall(r‘(?i)(?s)<script[^>]*>(.*?)</script>‘, response)通过将script脚本内的内容提取出来，通过一些正则来获取，最后输出。但这种方式准确度很低，只能用于辅助，不太适合自动化扫描。
它里面有内置一些参数，在检测时会将这些参数也一起发送
blindParams = [ # common paramtere names to be bruteforced for parameter discovery
‘redirect‘, ‘redir‘, ‘url‘, ‘link‘, ‘goto‘, ‘debug‘, ‘_debug‘, ‘test‘, ‘get‘, ‘index‘, ‘src‘, ‘source‘, ‘file‘,
‘frame‘, ‘config‘, ‘new‘, ‘old‘, ‘var‘, ‘rurl‘, ‘return_to‘, ‘_return‘, ‘returl‘, ‘last‘, ‘text‘, ‘load‘, ‘email‘,
‘mail‘, ‘user‘, ‘username‘, ‘password‘, ‘pass‘, ‘passwd‘, ‘first_name‘, ‘last_name‘, ‘back‘, ‘href‘, ‘ref‘, ‘data‘, ‘input‘,
‘out‘, ‘net‘, ‘host‘, ‘address‘, ‘code‘, ‘auth‘, ‘userid‘, ‘auth_token‘, ‘token‘, ‘error‘, ‘keyword‘, ‘key‘, ‘q‘, ‘query‘, ‘aid‘,
‘bid‘, ‘cid‘, ‘did‘, ‘eid‘, ‘fid‘, ‘gid‘, ‘hid‘, ‘iid‘, ‘jid‘, ‘kid‘, ‘lid‘, ‘mid‘, ‘nid‘, ‘oid‘, ‘pid‘, ‘qid‘, ‘rid‘, ‘sid‘,
‘tid‘, ‘uid‘, ‘vid‘, ‘wid‘, ‘xid‘, ‘yid‘, ‘zid‘, ‘cal‘, ‘country‘, ‘x‘, ‘y‘, ‘topic‘, ‘title‘, ‘head‘, ‘higher‘, ‘lower‘, ‘width‘,
‘height‘, ‘add‘, ‘result‘, ‘log‘, ‘demo‘, ‘example‘, ‘message‘]很好的思路，后面我的扫描器中也使用了这一点，从乌云镜像XSS分类中提取出了top10参数，在扫描时也会将这些参数加上。
如果参数可以回显，那么通过html解析就可以获得参数位置，分析回显的环境(比如是否在html标签内，是否在html属性内，是否在注释中，是否在js中)等等，以此来确定检测的payload。
后面我的扫描器的检测流程也是这样，非常准确和效率，不过Xsstrike分析html是自己写的分析函数，刚开始我也想直接用它的来着，但是这个函数内容过多，调试困难，代码也很难理解。
其实如果把html解析理解为html的语义分析，用python3自带的html提取函数很容易就能完成这一点。
XSStrike让我学习到了新一代xss扫描器应该如何编写，但新一代xss扫描器的payload是在Xray上学到的。
由于Xray没有开源，所以就通过分析日志的方式来看它的工作原理。
<html>
<body>
<a href="?q=1&w=2&e=3&r=4&t=5" />
<script>
<php
foreach($_GET as $key => $value){
// $_GET[$key] = htmlspecialchars($value);
}
$q = $_GET["q"];
$w = $_GET["w"];
$e = $_GET["e"];
$r = $_GET["r"];
$t = $_GET["t"];
if(stripos($q,"prompt") > 0){
die("error");
}
$var = ‘var a = "‘.$q.‘";‘;
echo $var;
>
</script>
<div>
<textarea><?php echo $w;?></textarea>
</div>
<input style="color:<?php echo $e;?>" value="<?php echo $r;?>"/>
<!--
this is comment
<?php echo $t;?>
-->
</body>
</html>简单写了一个脚本，用来分别测试xss在script，style内，html标签内，注释这几种情况下xray的发包过程。
1.对于在script的脚本内的回显内容，对于以下case
<script>
$var = ‘var a = "‘.$_GET[‘q‘].‘";‘;
echo $var;
</script>xray顺序发送了以下payload:pdrjzsqc，"-pdrjzsqc-",</sCrIpT><ojyrqvrzar>
最后会给出payload,但这个包并没有发送。后面把prompt作为关键词屏蔽，发现最后还是给出这个payload。
还有一种情况，在script中的注释中输出
<html>
<body>
<script>
var a = 11;
// inline <?php echo $_GET["a"];?>
/* <?php echo $_GET["b"];?> */
</script>
</body>
</html>xray会发送\n;chxdsdkm;//来判定，最后给出payload \n;prompt(1);//
2.对于在标签内的内容，对于以下case
<textarea><?php echo $_GET["w"];?></textarea>
xray顺序发送了以下payload:spzzmsntfzikatuchsvu,</tExTaReA><lixoorqfwj>，当确定尖括号没有被过滤时，会继续发送以下payload:</TeXtArEa>sCrIpTjhymehqbkrScRiPt,</TeXtArEa>iMgSrCoNeRrOrjhymehqbkr>,</TeXtArEa>SvGoNlOaDjhymehqbkr>,</TeXtArEa>IfRaMeSrCjAvAsCrIpTjhymehqbkr>,</TeXtArEa>aHrEfJaVaScRiPtjhymehqbkrClIcKa,</TeXtArEa>iNpUtAuToFoCuSoNfOcUsjhymehqbkr>,进行关键词的试探，最后给出payload为</TeXtArEa><img src=1>
3.对于在style里内容，以下case
<input style="color:<?php echo $_GET["e"];?>" />
xray顺序发送了以下payload:kmbrocvz,expression(a(kmbrocvz))
4.对于在html标签内的内容，以下case
<input style="color:3" value="<?php echo $_GET["r"];?>"/>
xray顺序发送了以下payload:spzzmsntfzikatuchsvu,"ljxxrwom=",‘ljxxrwom=‘,ljxxrwom=,当确认引号没有被过滤时，会继续发送以下payload："><vkvjfzrtgi>,">ScRiPtvkvjfzrtgiScRiPt,">ImGsRcOnErRoRvkvjfzrtgi>,">SvGoNlOaDvkvjfzrtgi>,">iFrAmEsRcJaVaScRiPtvkvjfzrtgi>,">aHrEfJaVaScRiPtvkvjfzrtgicLiCkA,">InPuTaUtOfOcUsOnFoCuSvkvjfzrtgi>," OnMoUsEoVeR=xviinqws,最后可以确定payload为"><img src=1>,"OnMoUsEoVeR=prompt(1)//
如果针对此类case：
<img src=1 onerror="a<?php echo htmlspecialchars($_GET["a"]);?>" />
xray返回payload为prompt(1)，说明xray会把onerror后面的内容当作JavaScript脚本来执行，如果把onerror改为onerror1，同样会返回prompt。在awvs规则中也看到过类似的规则
parName == "ONAFTERPRINT" ||
parName == "ONBEFOREPRINT" ||
parName == "ONBEFOREONLOAD" ||
parName == "ONBLUR" ||
parName == "ONERROR" ||
parName == "ONFOCUS" ||
parName == "ONHASCHANGE" ||
parName == "ONLOAD" ||
parName == "ONMESSAGE" ||
parName == "ONOFFLINE" ||
parName == "ONONLINE" ||
parName == "ONPAGEHIDE" ||
parName == "ONPAGESHOW" ||
parName == "ONPOPSTATE" ||
parName == "ONREDO" ||
parName == "ONRESIZE" ||
parName == "ONSTORAGE" ||
parName == "ONUNDO" ||
parName == "ONUNLOAD" ||
parName == "ONBLUR" ||
parName == "ONCHANGE" ||
parName == "ONCONTEXTMENU" ||
parName == "ONFOCUS" ||
parName == "ONFORMCHANGE" ||
parName == "ONFORMINPUT" ||
parName == "ONINPUT" ||
parName == "ONINVALID" ||
parName == "ONRESET" ||
parName == "ONSELECT" ||
parName == "ONSUBMIT" ||
parName == "ONKEYDOWN" ||
parName == "ONKEYPRESS" ||
parName == "ONKEYUP" ||
parName == "ONCLICK" ||
parName == "ONDBLCLICK" ||
parName == "ONDRAG" ||
parName == "ONDRAGEND" ||
parName == "ONDRAGENTER" ||
parName == "ONDRAGLEAVE" ||
parName == "ONDRAGOVER" ||
parName == "ONDRAGSTART" ||
parName == "ONDROP" ||
parName == "ONMOUSEDOWN" ||
parName == "ONMOUSEMOVE" ||
parName == "ONMOUSEOUT" ||
parName == "ONMOUSEOVER" ||
parName == "ONMOUSEUP" ||
parName == "ONMOUSEWHEEL" ||
parName == "ONSCROLL" ||
parName == "ONABORT" ||
parName == "ONCANPLAY" ||
parName == "ONCANPLAYTHROUGH" ||
parName == "ONDURATIONCHANGE" ||
parName == "ONEMPTIED" ||
parName == "ONENDED" ||
parName == "ONERROR" ||
parName == "ONLOADEDDATA" ||
parName == "ONLOADEDMETADATA" ||
parName == "ONLOADSTART" ||
parName == "ONPAUSE" ||
parName == "ONPLAY" ||
parName == "ONPLAYING" ||
parName == "ONPROGRESS" ||
parName == "ONRATECHANGE" ||
parName == "ONREADYSTATECHANGE" ||
parName == "ONSEEKED" ||
parName == "ONSEEKING" ||
parName == "ONSTALLED" ||
parName == "ONSUSPEND" ||
parName == "ONTIMEUPDATE" ||
parName == "ONVOLUMECHANGE" ||
parName == "ONWAITING" ||
parName == "ONTOUCHSTART" ||
parName == "ONTOUCHMOVE" ||
parName == "ONTOUCHEND" ||
parName == "ONTOUCHENTER" ||
parName == "ONTOUCHLEAVE" ||
parName == "ONTOUCHCANCEL" ||
parName == "ONGESTURESTART" ||
parName == "ONGESTURECHANGE" ||
parName == "ONGESTUREEND" ||
parName == "ONPOINTERDOWN" ||
parName == "ONPOINTERUP" ||
parName == "ONPOINTERCANCEL" ||
parName == "ONPOINTERMOVE" ||
parName == "ONPOINTEROVER" ||
parName == "ONPOINTEROUT" ||
parName == "ONPOINTERENTER" ||
parName == "ONPOINTERLEAVE" ||
parName == "ONGOTPOINTERCAPTURE" ||
parName == "ONLOSTPOINTERCAPTURE" ||
parName == "ONCUT" ||
parName == "ONCOPY" ||
parName == "ONPASTE" ||
parName == "ONBEFORECUT" ||
parName == "ONBEFORECOPY" ||
parName == "ONBEFOREPASTE" ||
parName == "ONAFTERUPDATE" ||
parName == "ONBEFOREUPDATE" ||
parName == "ONCELLCHANGE" ||
parName == "ONDATAAVAILABLE" ||
parName == "ONDATASETCHANGED" ||
parName == "ONDATASETCOMPLETE" ||
parName == "ONERRORUPDATE" ||
parName == "ONROWENTER" ||
parName == "ONROWEXIT" ||
parName == "ONROWSDELETE" ||
parName == "ONROWINSERTED" ||
parName == "ONCONTEXTMENU" ||
parName == "ONDRAG" ||
parName == "ONDRAGSTART" ||
parName == "ONDRAGENTER" ||
parName == "ONDRAGOVER" ||
parName == "ONDRAGLEAVE" ||
parName == "ONDRAGEND" ||
parName == "ONDROP" ||
parName == "ONSELECTSTART" ||
parName == "ONHELP" ||
parName == "ONBEFOREUNLOAD" ||
parName == "ONSTOP" ||
parName == "ONBEFOREEDITFOCUS" ||
parName == "ONSTART" ||
parName == "ONFINISH" ||
parName == "ONBOUNCE" ||
parName == "ONBEFOREPRINT" ||
parName == "ONAFTERPRINT" ||
parName == "ONPROPERTYCHANGE" ||
parName == "ONFILTERCHANGE" ||
parName == "ONREADYSTATECHANGE" ||
parName == "ONLOSECAPTURE" ||
parName == "ONDRAGDROP" ||
parName == "ONDRAGENTER" ||
parName == "ONDRAGEXIT" ||
parName == "ONDRAGGESTURE" ||
parName == "ONDRAGOVER" ||
parName == "ONCLOSE" ||
parName == "ONCOMMAND" ||
parName == "ONINPUT" ||
parName == "ONCONTEXTMENU" ||
parName == "ONOVERFLOW" ||
parName == "ONOVERFLOWCHANGED" ||
parName == "ONUNDERFLOW" ||
parName == "ONPOPUPHIDDEN" ||
parName == "ONPOPUPHIDING" ||
parName == "ONPOPUPSHOWING" ||
parName == "ONPOPUPSHOWN" ||
parName == "ONBROADCAST" ||
parName == "ONCOMMANDUPDATE" ||
parName == "STYLE"awvs会比较参数名称来确定。在后面的自动化扫描中，发现这种方式的误报还是很高，最后我将这种情况调整到了awvs的方式，只检测指定的属性key。
从这两处细微的差别可以看到，awvs宁愿漏报也不误报，结果会很准确，xray更多针对白帽子，结果会宽泛一些。
5.对于在html注释内的内容，以下case
<!--
this is comment
<?php echo $t;?>
-->
xray顺序发送了以下payload:spzzmsntfzikatuchsvu,--><husyfmzvuq>,--!><oamtgwmoiz>，和上面类似，当确定-->或--!>没有过滤时，会发送
以 --> 或 --!> 开头，添加如下内容
<bvwpmjtngz>
sCrIpTbvwpmjtngzsCrIpT
ImGsRcOnErRoRbvwpmjtngz>
sVgOnLoAdbvwpmjtngz>
iFrAmEsRcJaVaScRiPtbvwpmjtngz>
aHrEfJaVaScRiPtbvwpmjtngzcLiCkA
InPuTaUtOfOcUsOnFoCuSbvwpmjtngz>Awvs的扫描规则很多，针对的情况也很多，没有仔细看它的工作方式是怎样的，主要是看它的payload以及检测的情况，和上面两种查漏补缺，最终合成了我的xss扫描器～比如它会对meta标签的content内容进行处理，会对你srcipt，src等tag的属性处理，也有一些对AngularJs等一些流行的框架的XSS探测payload。
我的XSS扫描器就是综合上面三种扫描器而来，如果仔细观察，还会发现上面扫描器的一些不同寻常的细节。
比如xray不会发送xss的payload，都是用一些随机字符来代替，同时也会随机大小写对一些标签名称，属性名称等等。
这些精致的技巧我的扫描器也都一一吸取了，嘿嘿！
我的扫描器扫描流程是这样的
发送随机flag -> 确定参数回显 -> 确定回显位置以及情况(html，js语法解析) -> 根据情况根据不同payload探测 -> 使用html，js语法解析确定是否多出来了标签，属性，js语句等等
使用html语法树检测有很多优势，可以准确判定回显所处的位置，然后通过发送一个随机payload，例如<Asfaa>，再使用语法检测是否有Asfaa这个标签，就能确定payload是否执行成功了。
html语法树用python自带的库
from html.parser import HTMLParser
js检测也是如此，如果回显内容在JavaScript脚本中，发送随机flag后，通过js语法解析只需要确定Identifier和Literal这两个类型中是否包含，如果flag是Identifier类型，就能直接判断存在xss，payload是alert(1)//，如果flag是Literal类型，再通过单双引号来闭合进行检测。
整个xss扫描代码不过1000行，但debug的过程是道阻且长。
本地靶机测试后就对在线的靶机进行了测试 https://brutelogic.com.br/knoxss.html
查漏补缺后就开始了自动化扫描。
整个自动化架构如下
经过了不懈的改造，优化了检测逻辑，加入了去重处理后，现在不仅扫描的慢而且推送的消息也变少了。
经过一段时间对src的扫描后，成功还是挺多的（很多都归功于爬虫）
甚至发现了微软分站某处xss
未完，待续。。。
标签：ofo sel frame ima onkeyup show 思路 title 反射
原文地址：https://blog.51cto.com/14425409/2471506
