CVE-2021-38493: High severity firefox esr vulnerability

Published Sep 7, 2021
·
Updated

Mozilla developers Gabriele Svelto and Tyson Smith reported memory safety bugs present in Firefox 91 and Firefox ESR 78.13. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code.

Other sources

Mozilla developers reported memory safety bugs present in Firefox 91 and Firefox ESR 78.13. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability affects Firefox ESR < 78.14, Thunderbird < 78.14, and Firefox < 92.

Mozilla developers Tyson Smith and Gabriele Svelto reported memory safety bugs present in Firefox 91 and Firefox ESR 78.13. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code.

Mozilla developers Tyson Smith and Gabriele Svelto reported memory safety bugs present in Thunderbird 78.13. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code.

Mozilla

Affected Software

6 affected componentsFixes available
Mozilla Firefox ESR<78.14
78.14
Mozilla Thunderbird<78.14
78.14
Mozilla Firefox<92.0
Mozilla Firefox ESR<78.14
Mozilla Thunderbird<78.14
Mozilla Firefox<92
92

Event History

Sep 7, 2021
CVE Published
12:00 AM
Nov 3, 2021
CVE Published
via MITRE·12:03 AM
Data Sourced
via MITRE·12:03 AM
DescriptionWeakness

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-2021-38493?

CVE-2021-38493 has a medium severity rating due to the potential for memory corruption leading to arbitrary code execution.

2

How do I fix CVE-2021-38493?

To fix CVE-2021-38493, update Firefox to version 92 or higher, or update Firefox ESR and Thunderbird to version 78.14.

3

Which versions of Firefox are affected by CVE-2021-38493?

CVE-2021-38493 affects Firefox versions up to 91, Firefox ESR versions up to 78.13, and Thunderbird versions up to 78.13.

4

Is CVE-2021-38493 exploitable?

Yes, with sufficient effort, the memory safety bugs related to CVE-2021-38493 could potentially be exploited to execute arbitrary code.

5

Who reported CVE-2021-38493?

CVE-2021-38493 was reported by Mozilla developers Gabriele Svelto and Tyson Smith.

Contact

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