What: Shares of cybersecurity solutions provider CyberArk Software (CYBR -2.15%) slumped on Friday following the company's fourth quarter earnings report. While CyberArk beat analyst estimates across the board, mixed guidance was not well received by the market. At 11:20 a.m. EST Friday, the stock was down about 11%.

So what: CyberArk reported quarterly revenue of $51.5 million, up 42% year over year and about $7.6 million higher than analysts were expecting. License revenue of $33 million was up 35% year over year, while maintenance and professional services revenue rose 55% to $18.4 million.

CyberArk reported non-GAAP EPS of $0.39, up from $0.21 during the prior-year period, and $0.19 higher than the average analyst estimate. On a GAAP basis, EPS of $0.28 was up from $0.19 during the fourth quarter of 2014. Much of this earnings increase was driven by a lower tax rate compared to the fourth quarter of 2014. If the tax rate had remained the same, GAAP EPS would have been about $0.22.

Now what: While CyberArk's fourth quarter results were solid, the company's guidance disappointed investors. Revenue guidance actually came in above analyst expectations, with the company expecting first-quarter revenue between $42.5 million and $43.5 million, and full-year revenue between $205 million and $207 million. Analysts were expecting $41.6 million and $202.3 million, respectively.

CyberArk's earnings guidance was what got the stock into trouble. The company expects non-GAAP EPS between $0.15 and $0.16 during the first quarter, and between $0.83 and $0.86 during the full year. Analysts, however, expected $0.17 and $0.91, putting CyberArk's guidance below expectations.

After years of fast-growing companies like CyberArk being valued based on their revenue growth, it seems that investors are starting to care more about earnings. CyberArk's results and guidance weren't really bad, but investors are demanding an awful lot in light of the current stock market turmoil.