When an application is installed, all
files included within an AIR installer
file are installed onto the user's
computer into an application
directory. All files within the
application directory tree are
assigned to the application sandbox
when the application is run. Content
in the application sandbox is allowed
the full privileges available to an
AIR application, including interaction
with the local file system.
Many AIR applications use only these
locally installed files to run the
application. However, AIR applications
are not restricted to just the files
within the application directory —
they can load any type of file from
any source. This includes files on the
user's computer as well as files from
external sources, such as those on a
local network or from the Internet.
File type has no impact on security
restrictions; loaded HTML files have
the same security privileges as loaded
SWF files from the same source.
(However, content in the application
sandbox is restricted from loading
JavaScript files from outside that
sandbox. Details are provided in the
developer documentation.)
Content in the application security
sandbox has access to AIR APIs that
content in other sandboxes is
prevented from using. For example,
only content in the application
security sandbox can read and write to
the local file system.
Some JavaScript techniques exist for
dynamically transforming strings into
executable code. Content in the
application security sandbox can only
use these techniques while code is
loading from application URLs. Using
these techniques within the
application sandbox would pose a
security risk. For example, an
application could inadvertently
execute a string loaded from a network
sandbox, and that string may contain
malicious code, such as code to delete
or alter files on the user’s computer
or to report back the contents of a
local file to an untrusted network
domain. Details are provided in the
developer documentation.
If the SWF is not in the Air applications sandbox (ie the Application folder) than it cannot cross-script with the AIR file. Here is the detailed description.