Apple is facing another public relations challenge after an app developer breached hundreds of its iTunes user accounts, triggering customer complaints about fraudulent activity, according to The Wall Street Journal. Only 400 of the 150 million iTunes users were affected, however the incident could put Apple's (AAPL) security measures to the test as the company continues its rollout of the iPhone 4 and the iPad, both of which include iTunes.

Apple said that it plans to require customers to enter their credit card security code more frequently to reduce the chances of another breach, according to The Journal.

Although the incident is unlikely to hurt company shares, it marks another challenge for Apple following an AT&T (T) leak of the email addresses of more than 100,000 iPad users last month. Meanwhile, Apple is facing several class action lawsuits brought by iPhone 4 owners alleging antenna problems. These issues are unlikely to affect sales in the near term, but sales could suffer down the road should additional security problems and consumer complaints arise.

"The company has had a very long string of successful product launches in recent years, but there can be no guarantee that such success will continue in the future," Kevin Hunt, senior technology analyst at Hapoalim Securities, wrote in a report. "iPad is the current hot product, and while initial purchases have been strong, if consumer uptake were to fall off, it is likely that Apple's stock price would suffer materially."

Other analysts say Apple's ability to quickly address security breaches underscores that the company is unlikely to suffer much lasting damage. Trip Chowdhry, a senior analyst who covers Apple at Global Equities Research, says that he doesn't believe the most recent breach presents a problem for Apple, rather it highlights the speed at which it banned the app developer behind the alleged scheme. It s such a chaotic environment -- the fact that they've been able to verify fraud and eliminate it again tells me that Apple has things in place and is ahead of the curve," he says.

Apple is scheduled to report third-quarter results on July 20, and analysts are predicting revenues from the iPhone and iPad will exceed expectations. For shareholders, the most significant risk at this point would be additional glitches on either product, says Chowdhry, but long-term investors should expect such problems to pass.