Preventing Access To SQL Server From Other Servers
Oct 9, 2007
I'm using MSSQL7, NT authentication and application roles so only my application can access the data. Also, other applications (like Excel) can not access the data and read it. So far, so good...
Yet, I noticed that if I try to access the SQL Server from another SQL Server on the network, it is allowed to see the list of tables, SP, etc. It is not allowed to open the table, but the Import/Export wizard is working and will allow retrieving data from the secured tables.
If I change to MSSQL authentication, any user will be able to access the data from my application and I don't want that either.
Unless I'm missing something, this is a big problem, especially today where any VPN connection with valid user name and password can actually log in to the domain and therefore connect to the database via SQL Server.
By the way, the server still must allow access to users via applications so logins must exist. I just don't want other SQL servers on the network to be able to connect to and import/export, view table and SP, etc.
I'm using MSSQL7, NT authentication and application roles so only my application can access the data. Also, other applications (like Excel) can not access the data and read it. So far, so good...
Yet, I noticed that if I try to access the SQL Server from another SQL Server on the network, it is allowed to see the list of tables, SP, etc. It is not allowed to open the table, but the Import/Export wizard is working and will allow retrieving data from the secured tables. If I change to MSSQL authentication, any user will be able to access the data from my application and I don't want that either.
Unless I'm missing something, this is a big problem, especially today where any VPN connection with valid user name and password can actually log in to the domain and therefore connect to the database via SQL Server.
By the way, the server still must allow access to users via applications so logins must exist. I just don't want other SQL servers on the network to be able to connect to and import/export, view table and SP, etc.
Is there a way to use trusted connections in ASP.NET and WinForm applications yet prevent users from accessing databases directly (outside of applications) ? I know the use of trusted connections are recommended for several reasons however I have a lot of applications that I need to prevent users from accessing databases directly outside of the applications themselves.
Does anyone know how to prevent a certain machine from accessing SQL server? We have users who use a generic username and password (i.e. one login for 15 users) and I need to prevent a certain machine (in a high risk location) from hitting my databases. Any ideas
We have built a .NET on SQL Server application with extensive business functionality and security. It uses SQL integrated security to control logon and access to the database objects. There is business logic built into the .NET code, so I don€™t want any chance that users access the tables directly through a tool such as Management Studio - many users need update, delete, insert on tables in order to use the applications functions. With integrated security they can logon through SQL Management Studio and change data in the tables directly.
How are people who are using integrated security for their business applications preventing logons through unauthorized tools or applications?
Hi allWe had a small problem when an ASP web page had a missing 'where' statementand updated all the records in the table. Luckily we could retrieve all thedata from the backups.How do you guys prevent this from happening in your large systems. Is theresome teqnique for controlling this, I would imagine if you had thousands ofrecords in a table and some one made a programming error, then theconsequences would be disastrous.is there a setting within SQL Server that could force SQL update commands tobe limited to a criteria and if no criteria is supplied then reject thecommandthanks in advanceAndy
I am implementing the security and add different windows domain group and also assign then appropriate rights and permission.
No i want that if some knows the "sa" password and want to connect to sql server 2005 via query analyzer then message should display to user that u can not login with sa login while using SQL Server Query analyzer.
Hello, I have a developer here who wants to be able to access two databases on different servers with the same query statement. Both servers have SQL Server 7.0 ??? Any suggesstions?
we have some Access databases that are password protected. I get an error when I try an access these through a Linked Server. If I remove the password there is no problem.
I have tried adding the password to the security Information with a user of admin but this fails with a 7303 error. Should I not use admin as the user ??
Hello,I have an sql server 2000 on the network and one installed locally inmy computer. I use access as front-end.I go through odbc to connect to the sql server on the network.I was wondering if it is possible to setup the access file to link toeither server.I need to do this because I would like to use the local server as testenvironment. I know I could achieve that by creating 2 users on my XPclient and having odbc liking depending of the users.Is any other way to do that without login and logoff everytime I wantto use a different database.thanks,Giovanni
I know the SQL syntax to join two tables in different databases on the ame server, but does anyone know if a SQL statement will allow you to join tables from different databases on different servers?
I have NT SQL 7 and Web Server on same box. I have a new server with W2K and SQL 2000 installed (no IIS). I am migrating the databases over and when done I will install W2K on the old box and it will remain the IIS Web server front end to the new SQL 2000 Server.
On the old configuration, IIS and SQL 7 on the same box, I added the IUSER to the database from the local computer users list when needed for web access. How do I add that user now that the boxes are seperate? The acccout is not a local account on the new machine and the account is a loca account on the other machine so it does not authenticate to the domain so I can't pull it in from there.
Having a little problem with linking to Access tables. I have an Access database that has in it, some linked tables. After setting up the linked server in SQL server, none of the linked tables in Access show up, only the tables that were created or imported show up.
Is there anything you can do to get the linked tables in Access to show up under the tables list in the SQL linked server?
Being an IT consultant, I have to visit a number of customers having applications running on SQL Servers that implement trusted connection security model. In addition, all of these companies have their own DOMAIN settings, and security implementation.
How can I access to databases without changing the DOMAIN settings of MY notebook? I do not want them to switch to SQL security model, and I do not want to create any security hole in those companies.
What shall I want from the system administrator so that I can login into their domain without changing my domain settings?
I am facing a strange issue with accessing data from SQL server 2000. We are using SQL Server authentication for connecting to SQL Server 2000 and ADO .Net SQL client in the application. The problem here is, we have databases installed in one of the servers in some other office location that is in different state but on same domain. We do development from two locations that is one from Virtual Machines hosted on servers where Database Servers are located and on our local desktops in India.
Now when I developed a test client in Virtual Machines which will call a web service to get datasetof some data and show them in DataGrid. When I run the test client in debug mode from Visual Studio 2003, then I am getting data in the DataGrid. Even when I just run the exe from Virtual Machine still I am getting data.
But when I copy debug folder of the test client to the local desktop in India and when I run the Test client I am not getting any data loaded on to the DataGrid. I am getting an empty dataset when I am running from the local desktop.
Also I have converted the VS2003 project to VS2005 and when I run the application from Local Desktop then I am getting the data loaded fine. I could not understand what is the problem, what is the difference between accessing data from VS2003 and VS2005 using webservice.
Is this a firewall issue or I am missing any thing here. The webservice method I am calling to get data is actually returning dataset when I am calling this method directly from the browser also and even through application in virtual machine.
I am still not able to come to terms with this problem. This is severely affecting our deployment. Please help us resolve this problem. Please let me know if you need more information.
I'm looking to deploy some SQL Server reports and I want to restrict the access that the users have. Currently when connecting to the reports site they have access to a lot of functionality through the header bar, for example - Properties - New Folder - New Data Source - My Subscriptions - Site Settings - Search etc.
How can I disbale or hide all these options so that all the user sees is the list of reports?
We have 1 machine running SQL Server 2005 x64 (64 bit). The other machine is backing this SQL Server up. It is a 32-bit machine, so it requires (?) a 32-bit version of SQL Server 2005.
Would this back-up machine work correctly on a database previously managed by a 64-bit machine and vice versa.
1 ALTER PROCEDURE links_GetAllLinks 2 @startRowIndex INT, 3 @maximumRows INT, 4 @sortExpression nvarchar(50) 5 AS 6 7 8 9 10 11 SET @startRowIndex = @startRowIndex + 1 12 --SELECT @TopicsFrom = CASE @TopicsDays WHEN '1' THEN DATEADD(day,-1,getdate()) WHEN '2' THEN DATEADD(day,-7,getdate()) WHEN '3' THEN DATEADD(day,-14,getdate()) WHEN '4' THEN DATEADD(month,-1,getdate()) WHEN '5' THEN DATEADD(month,-3,getdate()) WHEN '6' THEN DATEADD(month,-6,getdate()) WHEN '7' THEN DATEADD(year,-1,getdate()) ELSE DATEADD(year,-1,getdate()) END 13 -- populate the table CAST(getdate() as int) 14 15 16 IF @sortExpression LIKE '' 17 BEGIN 18 SET @sortExpression = 'links_Links.link_date' 19 END 20 DECLARE @sql nvarchar(4000) 21 SET @sql = 'Declare @Links TABLE 22 (RowNumber INT, 23 link_id INT, 24 cat_id INT, 25 cat_title VARCHAR(100), 26 sub_id INT, 27 sub_name VARCHAR(100), 28 link_aproved BIT, 29 link_name VARCHAR(100), 30 link_url varchar(100), 31 link_desc varchar(500), 32 link_date datetime, 33 link_rating INT, 34 link_ratingscount INT, 35 link_ratingvalue INT, 36 link_poster uniqueidentifier, 37 link_comments INT, 38 hit_date datetime);INSERT INTO @Links 39 SELECT ROW_NUMBER() OVER (ORDER BY ' + @sortExpression + '), links_Links.link_id, links_Links.cat_id, links_Categories.cat_title, links_Links.sub_id, links_SubCategories.sub_name, links_Links.link_aproved, links_Links.link_name, links_Links.link_url, links_Links.link_desc, links_Links.link_date, links_Links.link_rating, links_Links.link_ratingscount, (links_Links.link_rating/links_Links.link_ratingscount) as link_ratingvalue, links_Links.link_poster, links_Links.link_comments, links_Links.hit_date 40 FROM links_Links INNER JOIN 41 links_Categories ON links_Categories.cat_id = links_Links.cat_id INNER JOIN 42 links_SubCategories ON links_SubCategories.sub_id = links_Links.sub_id 43 WHERE links_Links.link_aproved = 1;SELECT * from @Links 44 WHERE RowNumber BETWEEN ' + CONVERT(nvarchar(10), @startRowIndex) + ' AND (' + CONVERT(nvarchar(10), @startRowIndex) + ' + ' + CONVERT(nvarchar(10), @maximumRows) + ') - 1' 45 46 47 48 EXEC sp_executesql @sql 49 50 51 RETURN at row 39, i define a field by dividing to values. I use these for ratings (finding the mean). The problem is, when a new link is submited, it has no ratings, so it performs a divide by zero. how do I check if the column "link_ratingscount" is zero? if it is, then return a zero, and if it is not zero, then do the divide?
I am building my first ASP.Net app from scratch and while working on the DAL I came across the problem of SQL Injection. I searched on the web and read different articles but I am still unsure about the answer. My question is should I add
Add in Parameters to my C# code to avoid SQL Injection. What is the best practice. I am unclear if the stored procedure already helps me avoid SQl Injection or if I need the add in parameters in the C# methods to make it work. I need some help. Thanks, Newbie
My C# update method in the DAL (still working on the code)
private static bool Update(AvatarImageInfo avatarImage) { //Invoke a SQL command and return true if the update was successful. db.ExecuteNonQuery("syl_AvatarImageUpdate", avatarImage.AvatarImageID, avatarImage.DateAdded, avatarImage.ImageName, avatarImage.ImagePath, avatarImage.IsApproved);
return true; }
I am using stored procedures to access the data in the database.
My update stored proc
set ANSI_NULLS ON set QUOTED_IDENTIFIER ON GO
ALTER PROCEDURE [dbo].[syl_AvatarImageUpdate] @AvatarImageIDint, @DateAddeddatetime, @ImageNamenvarchar(64), @ImagePathnvarchar(64), @IsApprovedbit AS BEGIN -- SET NOCOUNT ON added to prevent extra result sets from -- interfering with SELECT statements. SET NOCOUNT ON; BEGIN TRY UPDATE[syl_AvatarImages] SET [DateAdded]= @DateAdded, [ImageName]= @ImageName, [ImagePath]= @ImagePath, [IsApproved]= @IsApproved WHERE[AvatarImageID] = @AvatarImageID RETURN END TRY BEGIN CATCH --Execute LogError SP EXECUTE [dbo].[syl_LogError]; --Being in a Catch Block indicates failure. --Force RETURN to -1 for consistency (other return values are generated, such as -6). RETURN -1 END CATCH END
My problem is that the 'INSERT INTO' query that sends the records to thetable is dynamically compiled in VBA and and the target table has a twocolumn primary key. I have made a number of attempts at getting 'WHERENOT EXISTS' to cure the problem but so far without success and previouspostings have resulted in advice to create an 'ignore duplicates' index.This solved the problem in asmuch as it allowed the SQL to insert the records that did not alreadyexist but resulted in the message appearing every time the user ran thethe query. Whilst this is not a major problem it is vaguely irritatingand I would like to find a way to stop it happening. I suspect that thesolution may involve using the @@ERROR command but I am not sure of thesyntax.RegardsColin*** Sent via Developersdex http://www.developersdex.com ***
My site has come under attack from sql injections. I thought I hadthings handled by replacing all single quotes with two single quotes,akaReplace(inputString, "'", "''")Alas, clever hackers have still managed to find a way to drop columnsfrom some of my tables. Can anybody direct me towards a best practicedocument on preventing these attacks?Thank you thank you,Kevin
Hello Everyone, I have a web form that allows the user to select a time to reserve. I am trying to make it so that when a user selects a date to schedule something (which i have working) a drop down list will fill with times that have not been reserved. The data is stored in two tables: tblCalendar and tblTime. tblTime contains pkTimeID and times (which are all possible times to select from in half hour intervals). tblCalendar contains a few fields but timeID and date (which is in the format M/d/yyyy) are what I need to test against. timeID is the foreign key of pkTimeID. Basically when the user selects the date, a function gets called that will run a SELECT statement to get the times available. All of this works, I am able to fill the ddl with all times available no matter what the date is or what has already been reserved. I want to check if a time has been already selected based on the date selected by the user and only allow times not selected to be listed. After acheiving this I would like to prevent the immediate time before and immediate time after from being displayed because each reserved time will last for one hour but the data is stored in half hour increments. Any help/suggestions/links will be greatly appreciated. If I need to provide anything else please let me know. Thanks in advance, Brian
This morning I found that during the night someone hacked into my remote hosted SQL server 2005 database. Every record in a description field in each of three tables had everything after the first sentence replaced with the same URL. The three pages that used these tables badly infected anyone who viewed them in IE.I had my host restore the 12/30 backup, and I changed all the database and ftp passwords, now I want to be sure my code isn't giving anyone access. I'm using strongly typed datasets. This is my code behind code.Dim sCategory = Request.QueryString("cat")Dim ResourceAdapter As New ResourcesTableAdapters.ResourcesTableAdapterDim dF As Data.DataTable = ResourceAdapter.GetDataByCategory(sCategory)Dim numRows = dF.Rows.CountLabelCat.Text = sCategoryRepeater1.DataSource = dFRepeater1.DataBind() Is there anything I can do to better secure this? Oh, my connect string is in the web.config file only, but it isn't encrypted. I will be encrypting it today.Diane
Hi all.. I've been scouring the forums for about 6 hours to no avail. This is a really simple question. I'm trying to have a registration page that lets the user input name, email, desired username, and password. I want to check the username and email fields to make sure ppl cannot sign up twice. So from what I've gathered I have a couple of options:
1) i can set up a unique constraint on the database columns, 2) i can run a select statement before inserting, 3) i can store the whole database column in a variable then search through it.
My question is how to do option 2? All of my transactions are through a sqldatasource object in c#.
Hi I have a problem. Every time I select the first Item of a dropdownlist, it prevents the Insert to the database. There are 8 droplists on the page but the insert is only effected by the First Item of lstTheme selcetion. My Insert code is here: Any ideas?? Private Sub btnInsertChange_Click(ByVal sender As Object, ByVal e As System.Web.UI.WebControls.CommandEventArgs) Handles btnInsertChange.Command
I use paramaterized queries when using ad-hoc queries in my code-behind. Everywhere website I visit says to use stored procedures or paramaterized queries if stored procedures cannot be used. I understand how SQL injection attacks work, but could someone please enlighten me why a paramaterized query helps prevent these attacks? It seems to me that the text that is entered on the web form would just be passed into the paramater, but I'm obviously missing something. Thanks.
I have a schema/user called mstp who has tables in another schema/user. How do I prevent the mstp user from seeing those tables/data that do not belong to their schema?
example:
database xxxx has tables som.employees and mstp.employees The mstp user should only allowed access to mstp.employees and nothing else.
I have a table using an identity column as its Primary Key and twocolumns (table reduced for simplicity) EmployeeNumber and ArrivalTime.CREATE TABLE [tblRecords] ([ID] [bigint] IDENTITY (1, 1) NOT NULL ,[EmployeeNumber] [varchar] (10) COLLATE SQL_Latin1_General_CP1_CI_ASNOT NULL ,[ArrivalTime] [datetime] NOT NULL ,CONSTRAINT [PK_tblRecords] PRIMARY KEY CLUSTERED([ID]) ON [PRIMARY]) ON [PRIMARY]GOI have an insert procedure that checks for duplicates before insertinga new record:IF (SELECT TOP 1 [ID] FROM tblRecords WHERE EmployeeNumber =@SocialSecurity) IS NULLBEGININSERT INTO tblRecords(EmployeeNumber,ArrivalTime)VALUES (@EmployeeNumber, @ArrivalTime)SELECT SCOPE_IDENTITY()ENDELSESELECT 0 AS DuplicateRecordIn 99.9% of the cases, this works well. However, in the event that theinsert attempts are literally "ticks" apart, the "SELECT TOP 1..."command completes on both attempts before the first attempt completes.So I end up with duplicate entries if the procedure is called multipletimes vey quickly. The system needs to prevent duplicateEmployeeNumbers within the past 45 days so setting the EmployeeNumberto UNIQUE would not work. I can check for older entries (45 days ornewer) very easily, but I do not know how to handle the times when theprocedure is called multiple times within milliseconds. Would aTRANSACTION with a duplicate check after the INSERT with a ROLLBACKwork in this case? Any help is greatly appreciated!-E
The database is configured for single publisher, many subscribers,merge replication. The maintenance plan started to fail a couple ofmonths ago and the database would not get backed up. After clearingall the locks, I am able to backup the database manually. The locksreturn again and I'm not able to backup the database with themaintenance plan. How can I get around the lock issue or solve it sothat I can backup the database again?Thanks,Chris
