WASHINGTON—A Securities and Exchange Commission official on Monday pointed to last week’s $55 million hack of a digital-currency fund as an example of why regulators worry about the broader use of blockchain.

“This highlights a number of concerns that are really core to the SEC’s role, which is not only issues of disclosure, investor protection,” but also includes “the technology and the systems that underpin the markets,” said Gary Goldsholle, deputy director of the SEC’s trading and markets division, speaking during a panel...