This article was originally published on Feb. 26, and updated on July 22.

Chinese social network Weibo (NASDAQ:WB) has surged more than 130% over the past 12 months, fueled by quarter after quarter of double-digit sales growth and triple-digit earnings growth. Analysts expect that momentum to continue, with 60% sales growth and 84% earnings growth this year.

But as we know, high-growth stocks also usually come with some major risks. If you plan to buy Weibo, you should be aware of the five main risks facing the company today.

A businessman carefully removes a wooden block from a towering stack.

Image source: Getty Images.

1. It trades at over 100 times earnings

Weibo currently trades at 112 times its GAAP earnings and 51 times its non-GAAP earnings for fiscal 2016. Those lofty P/E ratios are much higher than the industry average of 37 for internet information providers, but they are supported by its 211% GAAP earnings growth and 167% non-GAAP earnings growth in fiscal 2016 Nonetheless, Weibo's high multiples still leave it highly exposed to big sell-offs in a frothy market.

2. It's not the biggest social network

Weibo is one of China's biggest social networks, but it's still dwarfed by Tencent's (NASDAQOTH:TCEHY) WeChat, the country's most popular mobile messaging app. WeChat's monthly active users rose 23% annually to 938 million last quarter.

WeChat isn't just a simple chat app. It's a monolithic "super app" that lets users share content through its "Moments" news feed, play integrated mobile games, hail cabs, order food, transfer money, make e-commerce purchases, and access other online-to-offline services -- all without leaving the app. The growth of that ecosystem is dangerous for any rival, like Weibo, which provides similar services.

WeChat's mobile app.

WeChat's mobile app. Image source: iTunes.

3. All those other Weibos

The term "weibo" means "microblog"" in Chinese. The Weibo we're discussing in this article was once the microblogging arm of online portal giant Sina (NASDAQ:SINA), which spun off Weibo as a separate company in 2014 and maintained a majority voting stake.

However, there are other rival weibos in China, including Tencent Weibo, Sohu (NASDAQ:SOHU) Weibo, and NetEase Weibo. All these weibos act as social extensions of these internet and media companies' ecosystems. None of these weibos is bigger than Sina Weibo, but they could eventually steal market share away from the company. Tencent Weibo is particularly dangerous, because it's integrated with QQ, its older PC-based messaging platform, which still has 861 million active users.

4. Its biggest backers could bar rival players

Weibo's two biggest stakeholders are Sina and e-commerce giant Alibaba. The support of Sina gives Weibo streamlined access to the portal site's news stories and content, while Alibaba integrates e-commerce and payment features into Weibo's app.

That support helps Weibo, but it could also potentially block Sina and Alibaba's rivals from integrating their services with the platform. That means Sina rival Sohu or Alibaba's business-to-consumer competitor JD.com probably won't partner with Weibo anytime soon. Both companies have already partnered with WeChat instead -- which could throttle Weibo's growth potential in the ongoing ecosystem wars in the Chinese internet market.

5. Censorship and regulatory challenges

Lastly, Weibo isn't a platform for free speech. The Chinese government expects Weibo to self-censor posts related to controversial subjects and frequently orders the company to delete posts. The government once threatened to shut down all of Sina's news services for spreading "illegal" information, and it recently forced Weibo to suspend its live video and audio services until they were properly licensed.

Weibo could also face regulatory pressures in the United States. The SEC has probed the accounting firms that audited U.S.-listed Chinese companies. If the SEC hits Weibo with a similar probe (although there's no evidence that it ever will), investors will undoubtedly start questioning the company's growth story.

The key takeaway

I believe that Weibo is a risky and volatile stock, but I still believe it has room to grow. Its impressive top- and bottom-line numbers, expanding user base, and strong growth in adjacent markets such as data licensing and live video streaming all indicate that it won't peak anytime soon. However, Weibo isn't for risk-averse investors, and you should fully understand these risks before buying the stock. 

Leo Sun owns shares of Tencent and Sina. The Motley Fool recommends NetEase, Sina, Sohu.com, and Weibo. The Motley Fool has a disclosure policy.