WASHINGTON — About 1,900 people whose names were in White House visitor logs from the end of Donald J. Trump’s presidency recently received letters alerting them that their Social Security numbers had been mistakenly posted online in January during an upload of data from the House committee investigating the Jan. 6 attack on the Capitol.
The letters, which were sent by the Government Publishing Office and which recipients reported receiving within the past week, came nearly three months after the security breach, during which the office uploaded White House visitor logs from December 2020 that were obtained by the Jan. 6 committee.
The visitor logs, which contained 1,694 full Social Security numbers and 178 partial Social Security numbers, were online between 9:16 p.m. Jan. 2 and 11:21 a.m. Jan. 4. The Government Publishing Office removed them shortly after being alerted to the data breach by a news outlet.
“We are sorry that this data breach occurred and sincerely apologize for any inconvenience or concern this may cause,” the letters state, according to a copy of one obtained by The New York Times.
The release of the personal information, which included the Social Security numbers of prominent Republicans, occurred as the Jan. 6 committee was scrambling to upload voluminous data before dissolving at the end of the last Congress. The panel had obtained the logs as it scrutinized what was happening inside the White House in the run-up to the attack on the Capitol, as Mr. Trump and his allies met to discuss ways for him to cling to power, including the idea of disrupting Congress’s counting of electoral votes slated for Jan. 6.
An inspector general review of the incident released last month blamed the data breach on a “‘perfect storm’ of rushed confusion.” The Government Publishing Office said it had adhered to agency practices by not editing or altering the thousands of pages of materials it received from the Jan. 6 committee before uploading them.
The office said the document containing the personal data had been fully downloaded 166 times and partially downloaded 10 times.
The Washington Post, which reported earlier on the data breach, said the unredacted Social Security numbers included at least three members of Mr. Trump’s cabinet, Republican governors and many allies of the former president. Gov. Kristi Noem of South Dakota and Ben Carson, the former housing secretary, were among those affected.
The office set up a section of its website to address the data breach, and pledged to “provide additional services to those who may have been affected.”
The Jan. 6 committee was dissolved on Jan. 3, 2023. Republicans, who now control the House, have begun their own investigation into the committee’s work.
Maggie Haberman contributed reporting.