This keeps Google CEO Sundar Pichai up at night

Google CEO Sundar Pichai told lawmakers on Tuesday that, despite a recent string of company controversies, there is a singular concern that trumps most others.

“Protecting the security of our users is something that really keeps me up at night,” Pichai said during testimony on Capitol Hill.

Pichai made the comments while discussing potential hacks, of which he said the company has faced “significant” attempts in the past.

Google said on Monday that a technical glitch on its Google Plus platform potentially exposed 52 million additional users than the 500,000 previously thought. The bug could have exposed user names, email addresses and occupations. The company will shut down Google Plus platform within 90 days, a faster pace than previously planned.

Google, including YouTube, is responsible for at least 90 percent of internet searches – a wide scale hack could impact a large swath of the global population.

Pichai also said the company had “no plans” to launch a censored version of its search engine in China, where lawmakers noted the company pulled out in 2010 partially over concerns that the government in Beijing was potentially gaining access to data. The project remains an internal effort only, he said.