CVE-2021-43529: Critical severity thunderbird vulnerability

Published Nov 3, 2021
·
Updated

Thunderbird versions prior to 91.3.0 are vulnerable to the heap overflow described in CVE-2021-43527 when processing S/MIME messages. Thunderbird versions 91.3.0 and later will not call the vulnerable code when processing S/MIME messages that contain certificates with DER-encoded DSA or RSA-PSS signatures.

Affected Software

3 affected componentsFixes available
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 Thunderbird<91.3.0

Event History

Nov 3, 2021
CVE Published
12:00 AM
Feb 16, 2023
CVE Published
via MITRE·12:00 AM
Data Sourced
via MITRE·12:00 AM
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-2021-43529?

The severity of CVE-2021-43529 is critical.

2

Which software versions are affected by CVE-2021-43529?

Thunderbird versions prior to 91.3.0 and certain Debian Thunderbird versions are affected.

3

How can I fix CVE-2021-43529?

Update Thunderbird to version 91.3.0 or later, or apply the appropriate Debian package upgrades.

4

What is the vulnerability description of CVE-2021-43529?

CVE-2021-43529 is a heap overflow vulnerability in Thunderbird when processing S/MIME messages.

5

Where can I find more information about CVE-2021-43529?

More information about CVE-2021-43529 can be found in the references provided.

Contact

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