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A SQL Injection attack and search engines
A few weeks after my previous posting of a SQL Injection Advisory link, a new SQL Injection attack came up. Here's a post describing it; it also includes other useful links: http://www.rtraction.com/blog/devit/sql-injection-hack-using-cast.html A search Read More...
Posted 05 August 08 12:07 by lcris | 0 Comments   
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New Microsoft Security Advisory on SQL Injection
This came up yesterday: http://www.microsoft.com/technet/security/advisory/954462.mspx . It has good information and links. Read More...
Posted 25 June 08 11:56 by lcris | 0 Comments   
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A discussion of password authentication schemes
I have talked in the past about how passwords for SQL logins are protected in SQL Server (see this post ). I would like to describe this scheme in a more generic way and compare it with the alternative of encrypting the passwords, because I have seen Read More...
Posted 09 May 08 01:45 by lcris | 0 Comments   
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Security in a nutshell
Here's an attempt to succintly describe why achieving security is difficult: The engineer wants to implement a program P that allows users to perform action A. The hacker looks at program P and wonders how can he use it to perform actions other than A. Read More...
Posted 23 April 08 01:48 by lcris | 0 Comments   
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SQL Server: Password policy FAQ
I am starting this post to collect frequent Q&A related to password policy. I plan to keep updating the post if anything new is worth adding to it. Note that this FAQ does not cover SQL Server Compact Edition. Also note that BOL stands for Books OnLine. Read More...
Posted 20 February 08 04:18 by lcris | 2 Comments   
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Can encryption make you more vulnerable?
A recent article brings up this question and argues that encrypting data at rest can open the door to a new range of security and usability problems. Speaking only of the security aspects, I both agree and disagree, so I'd like to add a few comments on Read More...
Posted 11 February 08 04:57 by lcris | 0 Comments   
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SQL Server undocumented password hashing builtins: pwdcompare and pwdencrypt
First, I must say that I don't know why these exist in an undocumented form. They have been around for a long time and a search on their names gets me back pages of hits. Being undocumented means that their actual implementation may change slightly from Read More...
Posted 31 October 07 11:08 by lcris | 0 Comments   
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Basic SQL Server Security concepts: SIDs, orphaned users, and loginless users
I am grouping here two topics (orphaned users and loginless users) that are actually very different, but I have often seen confusion between them, so I am covering them together in an attempt to dispel that confusion. In a previous discussion of logins Read More...
Posted 25 October 07 05:42 by lcris | 0 Comments   
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SQL Server 2005: A note about the use of certificates
To avoid any confusion, this post is not about the use of certificates for securing the communication between a client machine and the server; instead, this refers to the use of certificates created via the CREATE CERTIFICATE DDL. I am prompted in writing Read More...
Posted 04 October 07 08:59 by lcris | 1 Comments   
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SQL Server 2008: Transparent data encryption feature - a quick overview
I have kept silent on this feature while it was being developed, but as it has now been publicly advertised in various ways (being mentioned here , here , here , and here , for example), I think it is probably time to write a bit about it. Given that Read More...
Posted 03 October 07 04:55 by lcris | 2 Comments   
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Security and copy protection
I have been watching the SQL Server Security forum for several years now and there is one question that gets spawned about once a month under different titles. It invariably begins with a request for guidance on how to secure access to a database, which Read More...
Posted 24 September 07 03:57 by lcris | 0 Comments   
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Basic SQL Server Security concepts - ownership chaining: good and evil; schemas
At some point during SQL Server's history, its designers must have confronted the following problem: how to give someone permission to see parts of a table without giving him any permission on the table? Slices of a table are easily defined using views, Read More...
Posted 13 September 07 11:37 by lcris | 0 Comments   
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Basic SQL Server Security concepts - permissions and special principals: sa, dbo, guest
In a previous post , I talked about the various types of principals in SQL Server. Let's have a further look in this post at permissions and at some of the hardcoded principals that ship with any installation of SQL Server. Permissions are what allow Read More...
Posted 12 September 07 03:12 by lcris | 0 Comments   
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Beyond cracking: cybercrime
If you are following the security news, you will not be surprised by what I cover in this post. It's old news already for most people working in security. But it's worth discussing this more, to raise awareness. In a nutshell, the idea is that breaking Read More...
Posted 17 July 07 01:37 by lcris | 3 Comments   
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SQL Server 2005: About login password hashes
There seem to be a couple of misconceptions around the SQL Server handling of login passwords. Hopefully, by the end of this post, you will have a much clearer idea about what is going on under the covers. Note that this refers to the passwords of logins Read More...
Posted 30 April 07 09:22 by lcris | 1 Comments   
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