I am a big fan of a few social networking sites so I read with alarm a story on the Wall Street Journal’s blog about how it may be possible to figure out a person’s social security number from the information you provide on a social networking site. On sites such as Facebook or MySpace, you can list your hometown and date of birth as part of your profile. You would not think such information could lead to someone being able to guess what your Social Security number is, but it does.
In the study quoted in the article, a professor and a researcher first examined a pool of numbers of deceased people born from 1973 to 2003. The Social Security Administration (SSA) apparently releases these numbers to the public. The SSA assigns Social Security numbers (SSNs’) based on zip code – the first three digits represent a person’s zip code at birth. The researchers were able to detect similarities in numbers belonging to people who were born in the same state at around the same time. They were thus able to accurately determine the first five digits of a person’s social security number at least 90% of the time.
The article discusses a second study in which the same team gathered the SSNs of university students taken off off the internet. They were able to guess the first five digits of the SSNS 6.3% of the time. While this may not be a big percentage, the professor noted that a sharp cyber criminal could take advantage and figure out the loopholes to gather the information with a high degree of success.
So, today I’m going to wish a friend of mine who I see on Facebook a happy birthday and then tell her to take her date of birth off of the site.