FireEye Inc's quarterly revenue fell for the first time since its market debut in 2013 and the company said both chairman and chief financial officer would leave, sending its shares down as much as 20 percent.
The company's shares were the most actively traded after the bell on the Nasdaq.
FireEye said Chief Financial Officer Mike Berry would leave the company to pursue another opportunity, and appointed Frank Verdecanna as his replacement.
The company also said David DeWalt, who became chairman of the board when he stepped down as chief executive last year, has resigned.
FireEye also forecast revenue of $160 million-$166 million for the current quarter, missing average analysts' estimate of $176.6 million, according to Thomson Reuters I/B/E/S.
The company's billings, a closely watched indicator of future business, fell 14 percent in the quarter to $221.8 million. Analysts on average had estimated billings of $240.3 million, according to research firm FactSet StreetAccount.
The company is amid a transition to a software-as-a-service model (SaaS) from its traditional business that centered around the sale of physical boxes.
FireEye, which provides web, email and malware security to businesses and governments, said its revenue fell slightly to $184.7 million in the fourth quarter ended Dec. 31, from $184.8 million a year earlier.
The company's revenue missed estimates of $191 million.
Excluding items, FireEye reported a loss of 3 cents per share, beating analysts' estimate of a loss of 16 cents.
Net loss attributable to shareholders narrowed to $61.5 million, or 37 cents per share, from $136.1 million, or 87 cents per share.
(Reporting by Narottam Medhora in Bengaluru; Editing by Shounak Dasgupta)