Getting Rid of Nasty Adobe Flash Cookies the Cool Linux Way

By: Carla Schroder
Friday, March 27, 2009 02:46:02 PM EST
URL: http://www.linuxplanet.com/linuxplanet/tutorials/6709/1/

Using find to See What We're Up Against

In Part 1 we learned about the not very well-known Adobe Flash cookies, how to find them on your Linux system, and how to use Adobe's Web-based Flash cookie manager. Today we're going to learn how to deal with Flash cookies using ordinary Linux commands, which unlike the Adobe manager are nice and fast and don't require an Internet connection. Linux has the advantage for nuking Flash cookies and keeping them nuked. If you want to pick and choose which ones to allow and which ones to deny, the Adobe tool is probably the better option.

Using find to See What We're Up Against

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$ cd
$ find -iname '*.sol'

The first command makes sure we're back at the top level of our home directory, and then find will search starting from there and then dive into the sub-directories. -iname performs a case-insensitive filename search, and '*.sol' means "find all files with the .sol extension." If you have the Flash plugin installed you should see results like this:

/home/carla/.macromedia/Flash_Player/#SharedObjects/9WQLPZGG/d.scribd.com/ScribdViewer.swf/scribdSettings.sol
/home/carla/.macromedia/Flash_Player/#SharedObjects/9WQLPZGG/i.dell.com/s_br.sol
/home/carla/.macromedia/Flash_Player/#SharedObjects/9WQLPZGG/listen.grooveshark.com/main.swf/gslite.sol
/home/carla/.macromedia/Flash_Player/macromedia.com/support/flashplayer/sys/#s.ytimg.com/settings.sol
/home/carla/.macromedia/Flash_Player/macromedia.com/support/flashplayer/sys/#googleads.g.doubleclick.net/settings.sol
/home/carla/.macromedia/Flash_Player/macromedia.com/support/flashplayer/sys/#www.soundclick.com/settings.sol

Even if you never view Flash videos, adservers use Flash. Want to know how many there are? Pipe the output of find to wc (word count):

$ find -iname '*.sol' | wc -l
95

The -l option counts linebreaks. 95 Flash cookies! Why so many? What do they do? You can't read them like ordinary HTTP cookies because they are binary instead of plain text. If you're curious you can fire up a hex editor and see inside, which probably won't tell you much:

$ hexedit .macromedia/Flash_Player/#SharedObjects/9WQLPZGG/i.dell.com/s_br.sol

Hit Ctrl+c to close hexedit.

You can extract any plain-text bits and skip all the hexedecimal stuff with the strings command:

$ strings .macromedia/Flash_Player/#SharedObjects/9WQLPZGG/listen.grooveshark.com/main.swf/gslite.sol
TCSO
gslite
1localQueueRepresentation
autoplayID
queueID
cursorPosition
CsuppressPendingUploadNotification

Which still doesn't tell us much, but it never hurts to look; curiosity is a splendid virtue.

Using find for Search and Destroy

Once you verify that you have a batch of Flash cookies, find will find and delete them all in one command by using the powerful -exec option, like this:

$ find -iname '*.sol' -exec rm "{}" \;

This means "find all files with the extension .sol and delete them." rm is remove, or delete. "{}" means "replace me with the name of the current file being processed", and the semi-colon means "stop, there are no more commands to execute." The semi-colon must be escaped with the backslash because it has a special meaning to the Bash shell, and we don't want Bash mucking with it.

find is very fast and this will nuke all Flash cookies in an eyeblink. If you're nervous, you can use -ok instead of -exec and you'll be asked to verify each deletion:

$ find -iname '*.sol' -ok rm "{}" \;
$ < rm ... ./s_br.sol > ?

Type y for yes or n for no.