The Social Security Numbers of tens of thousands of Americans ended up in a searchable public database that provides access to the tax filing applications of Section 527 political organizations on the Internal Revenue Service's website.
According to OpenSecrets.org, 527s are "...tax-exempt group(s) organized under section 527 of the Internal Revenue Code to raise money for political activities including voter mobilization efforts, issue advocacy and the like."
The public information dissemination nonprofit, Public.Resource.Org, wrote a letter to the IRS [PDF] earlier this month requesting that the government's tax collector temporarily remove the forms from their website in order to properly redact the highly sensitive information.
In a phone interview, Carl Malamud, the founder of Public.Resource.Org, told Threatpost that the IRS exposed tens of thousands of Social Security Numbers at the least, and may have in fact exposed more than 100,000.
Continued : http://threatpost.com/irs-exposes-ssns-in-database-of-public-tax-filings/101261
Also:
IRS exposed Social Security numbers of tens of thousands of political donors
IRS mistakenly exposed thousands of Social Security numbers

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