What: Shares of Infoblox (NYSE:BLOX) surged on Tuesday following the company's fiscal first-quarter earnings report. Infoblox beat analyst estimates for both revenue and earnings, announced a share buyback program, and provided strong guidance for the second quarter. As of 12:15 p.m. EST Tuesday, the stock was up about 21%.

So what: Infoblox reported quarterly revenue of $94 million, up 40.9% year over year and about $6.4 million higher than analysts were expecting. The networking security company saw product revenue grow by 61.4% year over year, while services revenue jumped by 22.6%.

Non-GAAP earnings came in at $0.13 per share, up from $0.05 per share during the same period last year and $0.07 higher than the average analyst estimate. On a GAAP basis, the company posted a loss of $0.03 per share, an improvement compared to a loss of $0.18 per share during the same period last year.

In addition to beating analyst estimates, Infoblox announced a $100 million share repurchase program, half of which will be executed as an accelerated share repurchase. At the current market capitalization, this share buyback would reduce the share count by about 9%.

Now what: Guidance for the second quarter also beat analyst expectations. Infoblox expects revenue between $93 million and $95 million, above the average analyst estimate of $91.3 million, while non-GAAP EPS is expected between $0.12 and $0.14, well above analyst expectations of $0.07.

Infoblox's strong results come one week after a pair of analysts downgraded the stock, which sent shares tumbling. The stock has now more than recovered, and the concerns cited by the analysts weren't borne out by Infoblox's first-quarter results.

Timothy Green has no position in any stocks mentioned. The Motley Fool has no position in any of the stocks mentioned. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.