CVE-2021-29959: Medium severity Mozilla Firefox vulnerability

Published Jun 1, 2021
·
Updated

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.

Affected Software

17 affected componentsFixes available
Mozilla Firefox<89
89
Mozilla Firefox>=78.11.0<89.0
alpine/firefox>=78.11.0<89.0-r0
89.0-r0
alpine/firefox>=78.11.0<89.0-r0
89.0-r0
alpine/firefox>=78.11.0<89.0-r0
89.0-r0
alpine/firefox>=78.11.0<89.0-r0
89.0-r0
alpine/firefox>=78.11.0<89.0-r0
89.0-r0
alpine/firefox>=78.11.0<89.0-r0
89.0-r0
alpine/firefox>=78.11.0<89.0-r0
89.0-r0
alpine/firefox>=78.11.0<89.0-r0
89.0-r0
alpine/firefox>=78.11.0<89.0-r0
89.0-r0
alpine/firefox>=78.11.0<89.0-r0
89.0-r0
alpine/firefox>=78.11.0<89.0-r0
89.0-r0
alpine/librewolf<89.0-r0
89.0-r0
alpine/librewolf<89.0-r0
89.0-r0
alpine/librewolf<89.0-r0
89.0-r0
alpine/librewolf<89.0-r0
89.0-r0

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade Firefox to a version that resolves this vulnerability.

    Fixed in 89
  2. Upgrade

    Upgrade alpine/firefox to a version that resolves this vulnerability.

    Fixed in 89.0-r0
  3. Upgrade

    Upgrade alpine/librewolf to a version that resolves this vulnerability.

    Fixed in 89.0-r0

Event History

Jun 1, 2021
CVE Published
12:00 AM
Jun 24, 2021
CVE Published
via MITRE·01:16 PM
Data Sourced
via MITRE·01:16 PM
DescriptionWeakness
Data Sourced
via NVD·02:15 PM
DescriptionSeverityWeaknessAffected Software
Data Sourced
via OSV·02:15 PM
DescriptionSeverityAffected Software

Parent advisories

This vulnerability appears in the following advisories.

Peer vulnerabilities

Found alongside the following vulnerabilities.

Frequently Asked Questions

1

What is the severity of CVE-2021-29959?

The severity of CVE-2021-29959 is classified as moderate due to potential privacy risks.

2

How do I fix CVE-2021-29959?

To fix CVE-2021-29959, users should update Firefox to version 89 or later.

3

What is the impact of CVE-2021-29959?

The impact of CVE-2021-29959 is that it allows websites to potentially re-enable camera access without user consent after microphone use.

4

Which versions of Firefox are affected by CVE-2021-29959?

CVE-2021-29959 affects Mozilla Firefox versions up to 89.

5

Who is affected by CVE-2021-29959?

Users of Firefox versions up to 89 are affected by CVE-2021-29959.

Company

Resources

Contact

SecAlerts Pty Ltd.
132 Wickham Terrace
Fortitude Valley,
QLD 4006, Australia
info@secalerts.co
By using SecAlerts services, you agree to our services end-user license agreement. This website is safeguarded by reCAPTCHA and governed by the Google Privacy Policy and Terms of Service. All names, logos, and brands of products are owned by their respective owners, and any usage of these names, logos, and brands for identification purposes only does not imply endorsement. If you possess any content that requires removal, please get in touch with us.
© 2026 SecAlerts Pty Ltd.
ABN: 70 645 966 203, ACN: 645 966 203