Una cookie flash, Local Shared Object (LSO) (en español Objeto Local Compartido)es una colección de archivos tipo cookie almacenadas como archivo en computador del usuario. Las LSO son usadas por todas las versiones de Adobe Flash Player desde la versión 6 y posteriores de Macromedia hasta el ahora obsoleto Flash MX Player.^[1]

Contenido 1 Preocupaciones sobre la privacidad 2 User control 3 File locations 4 Programming 4.1 Editors and toolkits 4.2 Operating system support 5 References 6 Enlaces externos

Preocupaciones sobre la privacidad

Los reproductores Flash usan un modelo de aislamiento de procesos. Con la configuración por defecto, Adobe Flash Player no solicita el permiso del usuario para alojar las LSO en el disco duro. Las LSO contienen contienen unos datos tipo cookie alojadas en determinadas paginas webs o dominios. Cualquier tipo de datos pueden ser alojados, algunos de ellos que tienen que ver con la privacidad. Es más, con estas cookies, los bancos en linea, comerciantes o anunciantes pueden usar las LSO con fines comerciales.^[2]

Sin embargo, en orden de respetar la privacidad de los usuarios y por fines de seguridad, la versión actual de Flash no permite a las LSO a ser compartidas entre dominios. Por ejemplo, una LSO de "www.example.com" no puede leer una LSO creada por el dominio "www.example2.com".^[3]

User control

Local Shared Objects are not temporary files. Users can opt-out of them on a per-site basis by right-clicking and selecting 'Settings', or can opt-out globally by using the Global Storage Settings panel^[4] of the online Settings Manager at Adobe's website.

Adobe's Website Storage Settings panel was created to let users view and delete LSOs on a per-domain basis. It is also possible to completely disallow LSOs from a specific domain by setting the storage space to "0 KB"^[5] Add-on extensions have also been created for the Firefox Web browser, called Objection^[6] and Better Privacy that allow the user to view and delete LSOs.^[7]

File locations

The default storage location for LSO files is operating system-dependent. LSO files are typically stored with a ".SOL" extension, within each User's directory. Note that for self-executing flash applications run on the local machine will show up as being run on a website, in the folder localhost.

• Windows XP and Vista:
  • For Web sites: %APPDATA%\Macromedia\Flash Player\#SharedObjects\<random code>\<domain>\<path>\<object name>.sol
  • For AIR Applications, %APPDATA%\<AIR Application Reverse Domain Name>\Local Store\#SharedObjects\<flash filename>.swf\<object name>.sol

• Mac OS X:
  • For Web sites, ~/Library/Preferences/Macromedia/Flash Player/#SharedObjects/<random code>/<domain>/<path from webserver>/<object name>.sol
  • For AIR Applications, ~/Library/Preferences/<AIR Application Name>/Local Store/#SharedObjects/<flash filename>.swf/<object name>.sol
• Linux/Unix:
  • ~/.macromedia/Flash_Player/#SharedObjects/<domain>/<path>/<flash filename>.swf/<object name>.sol

Programming

The Flash Player allows Web content to read and write LSO data to the computer's local drive on a per-domain basis;^[8] such data may preserve session state and record user data and behavior.^[9]

A Flash application may store up to 100kb of data to user's hard drive (browser cookies have a limit of just 4kb).^[8] The defined storage sizes are 0kb, 10kb, 100kb, 1Mb, 10Mb, and Unlimited.^[10] If the current limit is exceeded, the user is shown a dialog requesting storage space of the next size. The user may override the amount manually by clicking the Flash application with right mouse button and selecting Settings; however, this applies only to the domain of the Flash movie. If the selected setting is smaller than the current data size, the data is deleted.

Global LSO settings may be amended by the user, by browsing Adobe's Web page that invokes Adobe's "Global Settings Manager" control panel.^{[10] [11]}

Editors and toolkits

Software	Website	Developer	First public release	Latest stable version	Cost (USD)	Open source	License	Programming language
SolVE	SolVE	Darron Schall	2004-09	0.2 (2004-10-15)	Plantilla:Free	Sí	CPL	Java
.sol Editor	.sol Editor	Alexis Isaac	2005-02	1.1.0.1 (2005-02-21)	Plantilla:Free	Sí	MPL	ActionScript, Delphi/Kylix
Dojo Toolkit	Dojo Toolkit	Dojo Foundation	2004	1.0.2 (2007-12-19)	Plantilla:Free	Sí	BSD, AFL	JavaScript
MAXA Cookie Manager	MAXA Cookie Manager	Maxa Research	?	3.2 (2009-02-02)	Plantilla:Nonfree 35	No	proprietary	?
PyAMF	PyAMF	Nick Joyce	2007-10-07	0.4 (2009-01-18)	Plantilla:Free	Sí	MIT	Python
SOLReader	SOLReader	Alessandro Crugnola	?	?	Plantilla:Free	No	?	C#, PHP[12]
s2x	s2x	Aral Balkan	?	?	Plantilla:Free	Sí	?	Python[13]

Operating system support

Software	Windows	Mac OS X	Linux	BSD	Unix
SolVE	Sí	Sí	No	No	No
.sol Editor	Sí	No	Sí[14]	Sí[14]	Sí[14]
Dojo Toolkit	Sí	Sí	Sí	Sí	Sí
MAXA Cookie Manager	Sí	No	No	No	No
PyAMF	Sí	Sí	Sí	Sí	Sí

References

Enlaces externos

• «New Technique for Tracking Web Site Visitors». Slashdot (2005-04-04). Consultado el 2007-12-05.
• «Tracking with Flash Cookies». InformIT (2007-10-05). Consultado el 2007-12-05.
• How to block Flash cookies
• Electronic Privacy Information Center on "Local Shared Objects"