RyoShin's Journal: Facebook Phone Number Folly

I, along with most of the Slashdot community, know much about social networking sites. I, probably unlike much of Slashdot, am a member of a few. One of these sites, Facebook, came under fire about a year ago for their News Feed feature, which allowed users to see updates made by their friends in one convenient form. This resulted in a massive and seemingly unexpected backlash by the Facebook crowd, which caused Facebook to lock it down only a few days later.

So users of Facebook are not ignorant of the privacy hazards that sharing information like that can lead to. However, it seems that some haven't learned their lesson. Through my own News Feed, I learned that one of my friends had recently joined a group. However, the group had a very odd title, almost like it was a personal journal entry. Curiosity got the best of me, and I clicked through to find out.

To my utter surprise and slight discomfort, I found that it was a group set up for someone that lost their phone. He had set up the phone for the express purpose of retrieving the phone numbers he had lost in the old one. This can seem like a mis-guided attempt with only one example, as doing this may be an easy way to notify all of your friends. Facebook does allow for closed groups- close the group, and only the friends you've invited can see your new phone number or post their own. Perhaps this poor fellow merely misunderstood how the process worked.

With this in mind, I decided to plug "phone lost" into Facebook's search engine. The result is so many groups that it stops counting at 500. Yet not all is lost; once again, this could be a matter of convenience, and other users had closed their group. I decided the best way to test this theory was to do a sample of the first three pages of results and compile some (simple) stats. (Note that all numbers are assumed unique, which may skew the results in favor of panic.)

Total Groups: 27 (Facebook returned the same group a few times)
Open Groups: 81%
Total Members: 523
Phone Numbers (with Area Code): 184
Phone Numbers (no area code): 14

Percentage of Group Members with posted numbers: 37%

Average Membership per Group: 19
Potential Amount of Numbers available (with 500 groups): 3515

Sadly, I was very wrong. The number of users willing to post their phone numbers in an open location such as that is worrisome. While Facebook does have the option to enter your number in your profile, it can be restricted only to friends. Furthermore, by default profiles are locked to friends-only. The combination of these two elements may have set a false sense of privacy within the users who did post their numbers.

A few users had the fore-thought to at least withhold their area code. Even so, Facebook provides their primary network (area, college, or high school), which could be used to figure out the area code in relatively short time. One group owner did ask for numbers to be e-mailed rather than posted, citing the desire not to broadcast them to Facebook. He was ignored by nine people.

While I hate the "Protect the Children" argument, I believe it has some merit in this case, and extends beyond that. These numbers are readily available for anyone on Facebook to use for their own malicious pleasure. Even if all they can do is leave psychotic voice messages at odd hours, it can still be enough to emotionally scar a person, as happened to another friend of mine earlier this year.

Still, it is no surprise that many in this generation, especially high schooler students, don't understand the potential ramifications for posting such personal information online. I do plan to contact Facebook and ask them to attempt to send out a notice to these users or Facebook in general, but even that may go ignored.

This is a non-issue

[linuxrocks123]

Phone numbers aren't exactly private information, man. They're available to anyone in the form of printed public directories called phone books.

Re:

[RyoShin]

Very true. But with phone books, the best you can get is a name, address, and phone number. Maybe sex if the name isn't ambiguous.

With Facebook, even locked profiles can provide more information that can be used to harass people. Just the user's default image can speak a lot about them.

There are much bigger privacy concerns, both within and without Facebook, I just found this phenomenon interesting enough to relate.