Facebook stock rose more than 2 percent in trading Thursday after CEO Mark Zuckerberg told reporters he had not seen a noticeable change in user behavior in the wake of the Cambridge Analytica data scandal.

"I don't think there has been any meaningful impact we've observed," Zuckerberg said, when asked if the tech giant has seen a change in the behavior of users or buying pattern of advertisers.

"But, look, it's not good," Zuckerberg continued. "Even if we can't really measure a change and the usage of a product, or the business or anything like that, it still speaks to people feeling like this is a massive breach of trust and that we have a lot of work to do to repair that."

As of the close of trading Wednesday, Facebook shares had fallen more than 16 percent since reports of the scandal surfaced March 17.

Zuckerberg also told reporters that most Facebook users should assume they have had their public information taken by third parties. The company believes most of its users who had a specific search function enabled have had their profile data scraped.

The content and delivery of Zuckerberg's message Wednesday gave the first optimistic outlook for the company in weeks, Deutsche Bank analysts wrote in a note Thursday.

"Zuckerberg's comments to reporters Wednesday afternoon suggesting it has not seen any meaningful user or advertiser impact, and his tone with reporters, suggest to us that the worst is likely behind [Facebook]," Deutsche Bank said.

The firm expects to hear more details about the issue, and further data policy changes, from Zuckerberg when the company reports its first quarter earnings.

Zuckerberg also said data from 87 million users had been harvested by Cambridge Analytica, a political research firm that provided information to the Trump presidential campaign. Earlier, it was estimated that data from 50 million users had been harvested without authorization.