CVE-2021-43543: XSS

Published Dec 7, 2021
·
Updated

Documents loaded with the CSP sandbox directive could have escaped the sandbox's script restriction by embedding additional content.

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·09:19 PM
Data Sourced
via MITRE·09:19 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-2021-43543?

CVE-2021-43543 is rated as a medium severity vulnerability.

2

How do I fix CVE-2021-43543?

To fix CVE-2021-43543, update Mozilla Thunderbird to version 91.4 or later, or update Firefox ESR to versions above 91.4.

3

Which software is affected by CVE-2021-43543?

CVE-2021-43543 affects Mozilla Thunderbird versions less than 91.4, Firefox ESR versions less than 91.4, and specific Debian packages of Firefox and Thunderbird.

4

What does CVE-2021-43543 allow attackers to do?

CVE-2021-43543 allows attackers to escape the sandbox's script restriction within documents loaded with the CSP sandbox directive.

5

Is CVE-2021-43543 a remote code execution vulnerability?

No, CVE-2021-43543 does not involve remote code execution but could lead to unauthorized content execution within the application's sandbox.

Contact

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