RingCentral, used by over 350,000 businesses, and Zhumu, a Chinese version of Zoom, also runs a hidden local web server on users’ computers. The same security vulnerabilities that were recently reported in Zoom for. macOS also affect two popular video conferencing software that under the hood, are just a rebranded version of. Zoom. The software update could not protect former customers who are not using the software anymore but have the vulnerable web-server still activated on their systems unknowingly.
Source: https://thehackernews.com/2019/07/zoom-ringcentral-vulnerabilities.html