04:55 AM EST, 12/02/2025 (MT Newswires) -- (Updates with attribution to Coupang ( CPNG ) in the second paragraph and reaction by the company in the fifth and sixth paragraphs.)

Coupang ( CPNG ) was under investigation by South Korean police Monday after the company suffered a massive data breach, news outlets reported.

Personal data of at 33.7 million customers of the e-commerce platform was leaked in a breach that authorities believe began months ago but wasn't discovered until Nov. 18, the company said in an email to MT Newswires.

Reports cited South Korea's Science Minister Bae Kyung-hoon as saying Sunday that perpetrators had "abused authentication vulnerabilities" in Coupang's ( CPNG ) servers and that officials would investigate whether the company violated personal information protection rules.

Reuters cited message board posts showing that more than 10,000 people were planning to join a potential class-action lawsuit against Coupang ( CPNG ).

Coupang ( CPNG ) said in an email that it became aware on Nov. 18 of an unauthorized data breach involving about 4,500 customer accounts and immediately notified authorities, including police.

"Coupang ( CPNG ) blocked the unauthorized access route, strengthened internal monitoring, and retained experts from a leading independent security firm," the company said. "The investigation is ongoing and Coupang ( CPNG ) continues to work with law enforcement and regulatory authorities."