Two U.S. senators asked Facebook Inc. on Tuesday about a possible security flaw in its messenger application designed for children that would allow adults to contact underage users without parental approval.

In a letter to the Menlo Park, California-based company’s chief executive officer Mark Zuckerberg, Sen. Ed Markey, D-Massachusetts, and Sen. Richard Blumenthal, D-Connecticut, pushed for “more transparency” around the alleged flaw in Facebook Messenger Kids’ app.

Sen. Ed Markey (D-MA). March 14, 2007. Photo: Diego M. Radzinschi/NLJ

The senators pointed to reports from The Verge that “in thousands of cases” children using Facebook Messenger Kids joined group chats with members who did not have parental approval.

The app is designed for users ages 6 through 12 years old and “therefore, must comply with the Children’s Online Privacy Protection Act,” the senators wrote. Both raised concerns over Facebook Messenger Kids previously in a 2017 letter alleging the app violated COPPA by collecting data from children under 13 without parental consent.

“Together, these issues point to a worrying pattern of lax privacy protections for kids on the Messenger Kids platform,” the senators said. Neither immediately responded to request for additional comment.

Tuesday’s probe comes as Big Tech faces increased scrutiny over privacy, especially for young children.

Google settled a multimillion-dollar fine with the U.S. Federal Trade Commission, the agency enforcing COPPA, over violations on subsidiary platform YouTube last month. The FTC hit video platform Musical.ly, also known as TikTok, with a record-setting $5.7 million COPPA violation fine in February.

Sen. Richard Blumenthal (D-CT) before the start of a Senate Judiciary Committee hearing July 31.

Less than two weeks ago, Facebook reached a $5 billion fine over privacy violations related to user data collection practices. A Facebook representative confirmed the company received Tuesday’s letter but declined further comment.

Senators gave Facebook until Aug. 27 to answer nine questions about the alleged Messenger Kids security flaw, including when Facebook became aware, if parents have been notified and if the company considers COPPA violations related to the flaw covered by its July FTC settlement.

“Children’s privacy and safety online should be Messenger Kids’ top priority,” the senators said. “Your company has a responsibility to meet its promise to parents that children are not exposed to unapproved contacts, a promise that it appears that Facebook has not fulfilled.”

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