Shares of Fortinet (NASDAQ: FTNT) tumbled 5% in after-hours trading on Wednesday, despite the cybersecurity firm reporting better-than-expected second-quarter results. The sharp decline appears to be driven by weaker-than-anticipated guidance for the upcoming quarter.

For the second quarter, Fortinet reported adjusted earnings per share of $0.64, surpassing the analyst consensus estimate of $0.59. Revenue came in at $1.63 billion, slightly above the expected $1.624 billion. The company's billings, a key metric for future revenue, grew 15% year-over-year to $1.78 billion.

However, investors seem to be focusing on Fortinet's third-quarter outlook, which fell short of expectations. The company forecasts adjusted earnings per share between $0.62 and $0.64 for Q3, compared to the $0.65 analysts were expecting. This conservative guidance suggests potential challenges in maintaining its recent growth trajectory amid an increasingly competitive cybersecurity landscape.

Despite the after-hours drop, Fortinet's long-term prospects remain strong. The company announced an expansion of its FortiCloud services, introducing new offerings in identity management, secure file storage, and communication. These additions aim to strengthen Fortinet's position in the rapidly evolving cybersecurity market and could potentially drive future growth.