CWE
416
Advisory Published
CVE Published
Updated

CVE-2021-4128: Use After Free

First published: Tue Dec 07 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.

Credit: security@mozilla.org

Affected SoftwareAffected VersionHow to fix
Firefox<95
95
Firefox<95.0
Apple iOS and macOS

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Parent vulnerabilities

(Appears in the following advisories)

Frequently Asked Questions

  • 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.

  • How do I fix CVE-2021-4128?

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

  • Who is affected by CVE-2021-4128?

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

  • What type of vulnerability is CVE-2021-4128?

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

  • Is CVE-2021-4128 exploitable?

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

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