CVE-2021-38495: High severity thunderbird vulnerability

Published Sep 7, 2021
·
Updated

Mozilla developers reported memory safety bugs present in Thunderbird 78.13.0. 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 Thunderbird < 91.1 and Firefox ESR < 91.1.

Other sources

Mozilla developers Tyson Smith, Christian Holler, and Gabriele Svelto reported memory safety bugs present in Firefox 91 and Firefox ESR 91.0. 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, Christian Holler, and Gabriele Svelto reported memory safety bugs present in Thunderbird 78.13.0. 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

4 affected componentsFixes available
Mozilla Thunderbird<91.1
91.1
Mozilla Firefox ESR<91.1
Mozilla Thunderbird<91.1
Mozilla Firefox ESR<91.1
91.1

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 CVE-2021-38495?

CVE-2021-38495 is a memory safety bug present in Firefox 91 and Firefox ESR 91.0.

2

Is CVE-2021-38495 exploitable?

Yes, with enough effort, CVE-2021-38495 could have been exploited to run arbitrary code.

3

Which software versions are affected by CVE-2021-38495?

Mozilla Firefox ESR versions up to exclusive version 91.1 and Mozilla Thunderbird versions up to exclusive version 91.1 are affected by CVE-2021-38495.

4

What is the severity rating of CVE-2021-38495?

CVE-2021-38495 is rated with a severity of 7 (high).

5

How do I fix CVE-2021-38495?

To fix CVE-2021-38495, update your Mozilla Firefox ESR or Mozilla Thunderbird to version 91.1.

Contact

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