CVE-2021-43539: Use After Free

Published Dec 7, 2021
·
Updated

Failure to correctly record the location of live pointers across wasm instance calls resulted in a GC occurring within the call not tracing those live pointers. This could have led to a use-after-free causing a potentially exploitable crash.

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<91.4
91.4
Mozilla Firefox<95
95
Mozilla Firefox ESR<91.4
91.4
Mozilla Firefox<95.0
Mozilla Firefox ESR<91.4.0
Mozilla Thunderbird<91.4.0
Debian Debian Linux=9.0
Debian Debian Linux=10.0
Debian Debian Linux=11.0

Event History

Dec 7, 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-2021-43539?

CVE-2021-43539 has a high severity rating due to its potential to cause a use-after-free vulnerability.

2

How do I fix CVE-2021-43539?

To fix CVE-2021-43539, update Mozilla Thunderbird to version 91.4 or later, and update Firefox and Firefox ESR to the respective fixed versions.

3

Which software versions are affected by CVE-2021-43539?

CVE-2021-43539 affects Mozilla Thunderbird versions prior to 91.4, Firefox versions before 95, and Firefox ESR versions prior to 91.4.

4

Can CVE-2021-43539 lead to system crashes?

Yes, CVE-2021-43539 can lead to crashes due to potential use-after-free errors.

5

What happens if I don't address CVE-2021-43539?

If CVE-2021-43539 is not addressed, it could allow attackers to exploit the vulnerability, potentially leading to crashes and unauthorized access.

Contact

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