Shares of Kuaishou Technology slid as much as 6% on Tuesday to HK$62.70 ($8.06), their lowest level since Nov. 21, after the Chinese short-video platform was hit by a cyberattack that disrupted its livestreaming services overnight.

The stock was on track for its biggest one-day percentage drop since Oct. 14 and was the worst performer on the Hang Seng Tech Index, which was down 0.5% in early trading.

Kuaishou, the closest domestic rival to TikTok’s Chinese version Douyin, said it experienced a livestreaming cyber incident at around 10 p.m. local time (1400 GMT) on Monday.

The company said it had activated its emergency response plan, adding that livestreaming functions on its app were gradually returning to normal, while some other services remained affected.

Kuaishou said it had reported the incident to police and relevant authorities and would pursue further legal remedies.

Chinese media reports and social media posts said many users were briefly exposed to vulgar, violent and other explicit livestreaming content on the platform on Monday night, which some described as “unprecedented.”