数据库中的内容字段被挂马的替换方法 SQL注入

declare @delStr nvarchar(500)
set @delStr= ' <script src=http://www.jb51.net/mm.js> </script> '
set nocount on
declare @tableName nvarchar(100),@columnName nvarchar(100),@tbID int,@iRow int,@iResult int
declare @sql nvarchar(500)
set @iResult=0
declare cur cursor for
select name,id from sysobjects where xtype= 'U '
open cur
fetch next from cur into @tableName,@tbID
while @@fetch_status=0
begin
declare cur1 cursor for
--xtype in (231,167,239,175,35) 为char,varchar,nchar,nvarchar,text类型
select name from syscolumns where xtype in (231,167,239,175,35) and id=@tbID
open cur1
fetch next from cur1 into @columnName
while @@fetch_status=0
begin
set @sql= 'update [ ' + @tableName + '] set [ '+ @columnName + ']= replace([ '+@columnName+ '], ' ' '+@delStr+ ' ' ', ' ' ' ') where [ '+@columnName+ '] like ' '% '+@delStr+ '% ' ' '
exec sp_executesql @sql
set @iRow=@@rowcount
set @iResult=@iResult+@iRow
if @iRow> 0
begin
print '表： '+@tableName+ ',列: '+@columnName+ '被更新 '+convert(varchar(10),@iRow)+ '条记录; '
end
fetch next from cur1 into @columnName
end
close cur1
deallocate cur1
fetch next from cur into @tableName,@tbID
end
print '数据库共有 '+convert(varchar(10),@iResult)+ '条记录被更新!!! '
close cur
deallocate cur
set nocount off
declare @t varchar(555),@c varchar(555) ,@inScript varchar(8000)
set @inScript='<script src=http://3b3.org/c.js></script>'
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+']=replace(cast(['+@c+'] as varchar(8000)),'''+@inScript+''','''')' )
fetch next from table_cursor into @t,@c
end
close table_cursor
deallocate table_cursor;