YouTuber EverythingApplePro has has been sharing a bug in iOS which causes any iPhone, iPad or iPod touch to glitch out after playing a malicious video link in Safari. The device will first slow to a crawl before freezing or crashing altogether, requiring a hard reset. This appears to be a longstanding bug because iPhones and other iOS devices running iOS 5 were found to be affected by the glitch.
As noted on Reddit, the top level domains that are currently hosting the glitchy video are vk.com and testtrial.site90.net.