Hackers have infected one of China's most popular social media applications on Apple's App Store, Chinese internet firm Tencent says.
WeChat, an instant messaging application developed by Tencent, has hundreds of millions of users in China and around the world.
"A security flaw, caused by an external malware, was recently discovered affecting iOS users only on WeChat version 6.2.5," Tencent said in a statement posted on the Wechat blog, adding the flaw had been repaired.
"There has been no theft and leakage of users' information or money."
iOS is the operating system used by Apple's hugely popular iPhone and iPad devices.