Facebook last week rushed to patch a bug that exposed the accounts of individuals who manage pages, after the weakness was exploited against several high-profile pages.
If a Facebook page’s administrator edits a post, users can keep track of the modifications with the “View edit history” feature. This feature should show the user exactly when changes were made to a post, but the recent bug also revealed the account (i.e. profile) of the individual who made the modification.
The accounts that control Facebook pages are hidden by default and they should not be displayed in the Edit History window. The issue may have had serious implications, particularly for page administrators who are trying to keep their identity secret.
According to Wired, the vulnerability was introduced on Thursday evening and it was present only until Friday morning. Facebook told Wired that it learned of the issue from a security researcher, but it’s unclear who that researcher is.
Despite the fact that the bug existed for less than a day, it was disclosed on websites such as 4chan and people quickly began abusing it against high-profile pages. The targeted pages included the ones belonging to President Donald Trump, Canadian Prime Minister Justin Trudeau, activist Greta Thunberg, anonymous street artist Banksy, Anonymous hacktivists, and rapper Snoop Dogg.
This is not the first time a vulnerability has exposed the administrators of Facebook pages. Roughly two years ago, a researcher discovered that an email invitation to like a Facebook page contained — in the email source code —- the name of the page’s administrator.
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