CVE-2021-23997: Use After Free

Published Apr 19, 2021
·
Updated

Due to unexpected data type conversions, a use-after-free could have occurred when interacting with the font cache. We presume that with enough effort this could have been exploited to run arbitrary code.

Affected Software

2 affected componentsFixes available
Mozilla Firefox<88
88
Mozilla Firefox<88.0

Event History

Apr 19, 2021
CVE Published
12:00 AM
Jun 24, 2021
CVE Published
via MITRE·01:25 PM
Data Sourced
via MITRE·01:25 PM
DescriptionWeakness

Parent advisories

This vulnerability appears in the following advisories.

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Frequently Asked Questions

1

What is the severity of CVE-2021-23997?

CVE-2021-23997 has a moderate severity rating due to the potential for exploitation leading to arbitrary code execution.

2

How do I fix CVE-2021-23997?

To fix CVE-2021-23997, update Mozilla Firefox to version 88 or later.

3

What versions of Firefox are affected by CVE-2021-23997?

CVE-2021-23997 affects all versions of Mozilla Firefox prior to version 88.

4

Can CVE-2021-23997 be exploited remotely?

Yes, CVE-2021-23997 could potentially be exploited remotely through crafted web content.

5

What is a use-after-free vulnerability in the context of CVE-2021-23997?

A use-after-free vulnerability like CVE-2021-23997 occurs when memory that has been freed is accessed, potentially leading to arbitrary code execution.

Contact

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