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Microsoft Dynamics GP "Encrypted" Using Caesar Cipher
scribblej writes "Many large companies use Microsoft's Dynamics GP product for accounting, and many of these companies use it to store credit card numbers for billing customers. Turns out these numbers (and anything else in GP) are encrypted only by means of a simple substitution cipher. This includes the master system password, which can be easily selected and decrypted from the GP database by any user. Quoting: '[Y]ou DON'T HAVE TO GIVE ACCESS TO THE DYNAMICS DATABASE. What that means is if you create a base user in GP, that user can log into the SQL server and run a select statement on the table containing the "encrypted" GP System password. Not good.'"
Update: 05/22 02:57 GMT by T : The original linked post has been revised in a few places; significantly, the following has been added as a correction: "By default, GP gives the user access to the DYNAMICS database but the user CANNOT login to the SQL server using SQL Enterprise Manager."
So, this Microsoft product uses what amounts to the same "encryption" that the CVS pserver protocol uses. Hilarious.
Check out my world simulator thingy.
You need to use the vocative case there, not the nominative.
Here's a text only cache of the page.
It's hard to believe that's how Micronians are made. Why don't we see it right now by having you both kiss one another?
Sorry... I didn't expect /. to pick this up, and didn't really warn Chris Kois that I'd submitted it. My fault.
Below is the original article:
I use the term "encryption" loosely in this article. As you read on, you'll realize why...
I've been doing some work on a plugin for Microsoft Dynamics GP, which is an accounting system aimed at Medium sized to Large businesses. To give you an idea of what type of application this is: There are companies that pay somewhere around $10,000-$15,000 to consultants or VARS (Value Added Resellers) to implement a Microsoft Dynamics GP solution for their business. Many of the VARs have their own plugins and solutions for Microsoft Dynamics GP, usually written in .NET or Dexterity. The process of installing and maintaining GP is an industry all it's own and it's not cheap for a company to maintain this accounting system.
I've been searching for the "encryption algorithm" or at least some way other way to "encrypt" data in GP in some other way than within Dexterity code. I was really hoping that there would be some .NET library that would do this for me, but I was never able to find anything that would help me do this. So, I became interested in what type of "encryption" this is. Somewhere (I can't remember where) I found something that indicated that the it's a symmetric key encryption algorithm. The message boards were not much help either. Anywhere I went, I basically saw this same type of statement, "the encryption algorithm is a closely guarded secret".
Today, while doing some testing, I noticed something with data that we were saving to a field which utilizes the GP "encryption". The plugin I was testing puts data in an encrypted field (not that it needs to because it's not sensitive in nature), and I was testing with the same values each time. As I would expect, I saw the same data stored in the field in the database for each row in the table. However, I noticed that one of the entries was different, by 2 characters. That seemed very odd to me. After looking at it some more and conducting some more tests, it looks like I simply miskeyed my test data, but it prompted me to take another look at this.
After trying a couple different combinations of test data, it became very obvious that changing only one character in the test data appeared to only alter 2 characters of the encrypted data. So I ran through a battery of tests, and came up with this:
Yep, it's basically your run-of-the-mill Substitution cipher. The worst part, there's evidence all over the place that this was a VERY weak encryption algorithm for awhile, but nobody seemed to pay any attention to it when people were asking how they could reset passwords of users in the database (Post 1 - Post 2)
I did some more searching, because there is ABSOLUTELY NO WAY THAT I AM THE ONLY ONE THAT SAW THIS... I found a good write up on the MSDN blogs that explains pretty well how the GP encryption was used (here).
The article is evidence to support a theory that I have, which is after GP moved to SQL server authentication, the encryption method didn't seem to be needed any longer so they never replaced. I don't know if the word was released to developers and integrators that the "encryption algorithm" wasn't ideal for storage of sensitive information, but I don't know how many plugins or customizations use it either.
EXCEPT.... Microsoft still uses it for their GP system password, which is the password needed to get to the Security Roles/Tasks and all the User Security related forms while in GP. What's even worse, if you create a new user, you have to give the user explicit rights to the company or companies you want the user to access, but you DON'T HAVE TO GIVE ACCESS TO THE DYNAMICS DATABASE. What that means is if you create a base user in GP, that user can log into the SQL server and run a select statement on the table containing the "encrypted" GP System password... Not good...
I created a
Ohg vg'f jnl zber frpher gung jnl
But it's way more secure that way
(mad cryptoquote skillz)
0 = 1 + e^(Alt something)
And storing credit card details in this way is in direct violation of the PCI-DSS which as a merchant the companies will have attested that they are in compliance with. If they get caught or worse leak data then there are severe financial penalties.
I have the displeasure of working with Great Plains regularly, and this isn't surprising at all.
A couple of points for the panic stricken:
1. Great Plains uses SQL logins and it hashes the passwords of users created from within GP. Since 9.0, it salts this hash using the sql server name. A GP user other than sa can NOT login to SQL Enterprise Manager with their GP credentials. That encryption has NOT been broken (yet). (That WOULD be a real problem.)
2. The ability to decrypt the System password is useless if you can't query the system password from the database. If your users have the ability to query any table in the database directly, then you have a bigger problem than weak encryption.
3. GP overlays role and task based security on top of the SQL login mechanism. Having the decrypted System Password is less useful if your application user doesn't have the ability to reach the User Setup or Security Options menus. These menus should be turned off for everyone not in the GP PowerUser role.
Is this great for GP? No. Neither is it the harbinger of the apocalypse.
-ellie