|Maintainer:||ManTech International Corporation|
mdd, also known as ManTech dd or Memory dd, is a command line program to acquire an image of the memory of a running Windows computer. The program has been included in the Helix incident response tool.
The current version of mdd [forensicswiki|mdd_1.3.exe] runs on Window XP to SP3 and Vista to SP 2, and may run on other versions. However, development seems to have stopped. For a more full-featured memory dumper, consider WinDD.
To execute mdd, you must start cmd.exe. The options are:
- -o filename - required to actually run mdd
- -w - license information
- -v - verbose
To run mdd, the account you are using must have administrator access to the machine you wish to image (however, it does not have to be the Administrator account; it only needs to be in the local Administrator group). The program works by installing a service, called mdd, although see below for problems.
These are the known problems with mdd.
This is a Windows Service Manager error. mdd executes by registering itself as a service, so it can run as administrator, although this does not mean you can run mdd without having administrator access. At the end of a normal execution, the service is deleted. However, mdd can accidentally leave the service installed, and this prevents further imaging. This could be caused by the system crashing (or an intentional system crash) during imaging, or by attempting to stop the imaging with control-c. If this happens, a knowledgeable Windows user will open up the Services tab in Computer Manager, but unfortunately, Windows has a wonderful feature that allows services, when they are registered, to state whether or not they wish to be seen in the Service Manager. This amazing concept allows services to run less visibly, and should be considered a class-a security flaw. Fortunately, there's a way around this, using the command line (cmd.exe).
- Run cmd.exe
- In cmd.exe, run "sc help" to see the service manager command line tool
- Run "sc query" to see all of the currently registered services, but note that this list will overflow the default line buffer of cmd.exe (this is adjustable, but not necessary for our purposes)
- Run "sc query mdd" and - ta-da - you'll see the mdd service
- Run "sc delete mdd" and it's gone, and mdd can now be run again.
John Judd will be entering text here.
In Vista, even if you are in the administrator group, you do not necessarily run programs with administrator access (this is actually a major improvement to the security model of Windows). You can start programs, including cmd.exe, with admin privileges, but in this case, that won't help. You will not be able to image to a Network Share from Vista. There is no known workaround. This problem may exist in Windows 7.