CVE-2021-43528: Medium severity thunderbird vulnerability

Published Dec 7, 2021
·
Updated

Thunderbird unexpectedly enabled JavaScript in the composition area. The JavaScript execution context was limited to this area and did not receive chrome-level privileges, but could be used as a stepping stone to further an attack with other vulnerabilities.

Affected Software

6 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<91.4
91.4
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·09:21 PM
Data Sourced
via MITRE·09:21 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-2021-43528?

CVE-2021-43528 is classified as a moderate severity vulnerability.

2

How do I fix CVE-2021-43528?

To fix CVE-2021-43528, upgrade Thunderbird to version 91.4 or later.

3

What versions of Thunderbird are affected by CVE-2021-43528?

CVE-2021-43528 affects all versions of Thunderbird prior to 91.4.

4

Does CVE-2021-43528 allow for remote code execution?

No, CVE-2021-43528 does not allow for remote code execution, but it enables JavaScript in a limited context.

5

Is there any workaround for CVE-2021-43528?

There are no known effective workarounds for CVE-2021-43528, so upgrading is recommended.

Contact

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