Cyber security firm FireEye Inc. (FEYE) - Get Report fell 12.1% to close at $16.19 in Thursday's trading after fourth-quarter earnings topped estimates but investors were wary on the company's 2019 predictions.

The California tech company posted adjusted earnings of 6 cents a share, 1 cent above estimates. Revenue of $218 million rose 6% from the same time a year ago and was at at the high end of the guidance range.

Still, predictions for the next quarter apparently made investors uneasy as shares fell to $16.30. For the first quarter of 2019, FireEye expects an adjusted loss per share of 4 to 2 cents on revenue of $208 million to $212 million. For the entire year, the company expects adjusted earnings of 17 cents to 21 cents on revenue ranging from $880 million to $890 million.

Yet, 2018 did go out well for FireEye, which closed the full year with revenue of $831 million, a 7% hike over the previous year. Adjusted earnings 8 cents a share cents, compared with a loss of 5 cents in 2017. 

"Our business continued to evolve toward a recurring subscription model," said Frank Verdecanna, chief financial officer, of FireEye, noting that "recurring subscriptions and support billings" were a boon to business of the year.

FireEye specializes in security technologies, threat intelligence, and consulting and has more than 7,700 customers across 67 countries.