CVE-2021-4128: Use After Free

Published Dec 7, 2021
·
Updated

When transitioning in and out of fullscreen mode, a graphics object was not correctly protected; resulting in memory corruption and a potentially exploitable crash.<br>This bug only affects Firefox on MacOS. Other operating systems are unaffected.. This vulnerability affects Firefox < 95.

Other sources

When transitioning in and out of fullscreen mode, a graphics object was not correctly protected; resulting in memory corruption and a potentially exploitable crash.This bug only affects Firefox on MacOS. Other operating systems are unaffected.

Mozilla

Affected Software

5 affected componentsFixes available
Mozilla Firefox<95
95
Mozilla Firefox<95.0
macOS
All of the following
Mozilla Firefox<95.0
macOS

Event History

Dec 7, 2021
CVE Published
12:00 AM
Dec 22, 2022
CVE Published
via MITRE·12:00 AM
Data Sourced
via MITRE·12:00 AM
DescriptionWeakness
Data Sourced
via NVD·08:15 PM
RemedyDescriptionSeverityWeaknessAffected Software

Parent advisories

This vulnerability appears in the following advisories.

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Frequently Asked Questions

1

What is the severity of CVE-2021-4128?

CVE-2021-4128 is classified as having a high severity due to potential memory corruption and exploitation risks.

2

How do I fix CVE-2021-4128?

To fix CVE-2021-4128, update Firefox to version 95 or higher.

3

Who is affected by CVE-2021-4128?

CVE-2021-4128 affects users running Firefox versions prior to 95 on MacOS.

4

What type of vulnerability is CVE-2021-4128?

CVE-2021-4128 is a memory corruption vulnerability that occurs during fullscreen transitions.

5

Is CVE-2021-4128 exploitable?

Yes, CVE-2021-4128 could potentially be exploited to cause crashes on affected systems.

Contact

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