CVE-2021-29959: Mozilla Firefox

Medium severity, CVSS 4.3. EPSS: 0.8% chance of exploitation in the next 30 days.

When a user has already allowed a website to access microphone and camera, disabling camera sharing would not fully prevent the website from re-enabling it without an additional prompt. This was only possible if the website kept recording with the microphone until re-enabling the camera. This vulnerability affects Firefox < 89.

Affected products

• Mozilla Firefox: from 78.11.0, before 89.0 (fixed in 89.0)

Published 2021-06-24. Last modified 2026-06-17.