CVE-2021-43534: High severity thunderbird vulnerability

Published Nov 2, 2021
·
Updated

Mozilla developers and community members Christian Holler, Valentin Gosu, and Andrew McCreight reported memory safety bugs present in Firefox 93 and Firefox ESR 91.2. 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 Christian Holler, Valentin Gosu, and Andrew McCreight reported memory safety bugs present in Thunderbird 91.2. 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 reported memory safety bugs present in Firefox 93 and Firefox ESR 91.2. 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 < 94, Thunderbird < 91.3, and Firefox ESR < 91.3.

Affected Software

12 affected componentsFixes available
debian/firefox
118.0.2-1
debian/firefox-esr
91.12.0esr-1~deb10u1115.3.1esr-1~deb10u1102.15.0esr-1~deb11u1115.3.1esr-1~deb11u1102.15.1esr-1~deb12u1115.3.0esr-1~deb12u1115.3.0esr-1115.4.0esr-1
debian/thunderbird
1:91.12.0-1~deb10u11:115.3.1-1~deb10u11:102.13.1-1~deb11u11:115.3.1-1~deb11u11:102.15.1-1~deb12u11:115.3.1-1~deb12u11:115.3.1-1
Mozilla Thunderbird<91.3
91.3
Mozilla Firefox<94
94
Mozilla Firefox ESR<91.3
91.3
Mozilla Firefox<94.0
Mozilla Firefox ESR<91.3.0
Mozilla Thunderbird<91.3.0
Debian Debian Linux=9.0
Debian Debian Linux=10.0
Debian Debian Linux=11.0

Event History

Nov 2, 2021
CVE Published
12:00 AM
Dec 8, 2021
CVE Published
via MITRE·09:20 PM
Data Sourced
via MITRE·09:20 PM
DescriptionWeakness
Data Sourced
via NVD·10:15 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-2021-43534?

The severity of CVE-2021-43534 is high.

2

Which versions of Firefox are affected by CVE-2021-43534?

Firefox versions up to and excluding 94 are affected by CVE-2021-43534.

3

How can I fix CVE-2021-43534 in Firefox?

To fix CVE-2021-43534 in Firefox, update to version 94 or higher.

4

Which versions of Firefox ESR are affected by CVE-2021-43534?

Firefox ESR versions up to and excluding 91.3 are affected by CVE-2021-43534.

5

How can I fix CVE-2021-43534 in Firefox ESR?

To fix CVE-2021-43534 in Firefox ESR, update to version 91.3 or higher.

Contact

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