CVE-2021-4129: Critical severity thunderbird vulnerability

Published Dec 7, 2021
·
Updated

Mozilla developers and community members Julian Hector, Randell Jesup, Gabriele Svelto, Tyson Smith, Christian Holler, and Masayuki Nakano reported memory safety bugs present in Firefox 94 and Firefox ESR 91.3. 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 and community members Julian Hector, Randell Jesup, Gabriele Svelto, Tyson Smith, Christian Holler, and Masayuki Nakano reported memory safety bugs present in Firefox 94. 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

Mozilla developers and community members Julian Hector, Randell Jesup, Gabriele Svelto, Tyson Smith, Christian Holler, and Masayuki Nakano reported memory safety bugs present in Thunderbird 91.3. 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.

Affected Software

6 affected componentsFixes available
Mozilla Thunderbird<91.4
91.4
Mozilla Firefox<95.0
Mozilla Firefox ESR<91.4.0
Mozilla Thunderbird<91.4.0
Mozilla Firefox<95
95
Mozilla Firefox ESR<91.4
91.4

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
DescriptionSeverityWeaknessAffected Software

Parent advisories

This vulnerability appears in the following advisories.

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Frequently Asked Questions

1

What is the severity of CVE-2021-4129?

CVE-2021-4129 has a medium severity rating due to memory safety issues in affected versions of Mozilla Firefox and Thunderbird.

2

How do I fix CVE-2021-4129?

To fix CVE-2021-4129, update your Mozilla Firefox or Thunderbird to version 95 or 91.4 respectively.

3

What versions of software are affected by CVE-2021-4129?

CVE-2021-4129 affects Mozilla Firefox up to version 94, Firefox ESR up to version 91.3, and Thunderbird up to version 91.3.

4

What are the potential impacts of CVE-2021-4129?

The potential impacts of CVE-2021-4129 include memory corruption that could lead to arbitrary code execution.

5

Who reported the CVE-2021-4129 vulnerability?

CVE-2021-4129 was reported by Mozilla developers and community members including Julian Hector, Randell Jesup, and others.

Contact

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