CVE-2021-23954: High severity thunderbird vulnerability

Published Jan 26, 2021
·
Updated

Using the new logical assignment operators in a JavaScript switch statement could have caused a type confusion, leading to a memory corruption and a potentially exploitable crash.

Affected Software

9 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-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<78.7
78.7
Mozilla Firefox<85.0
Mozilla Firefox ESR<78.7
Mozilla Thunderbird<78.7
Mozilla Firefox<85
85
Mozilla Firefox ESR<78.7
78.7

Event History

Jan 26, 2021
CVE Published
12:00 AM
Feb 26, 2021
CVE Published
via MITRE·02:10 AM
Data Sourced
via MITRE·02:10 AM
DescriptionWeakness

Parent advisories

This vulnerability appears in the following advisories.

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Frequently Asked Questions

1

What is the severity of CVE-2021-23954?

CVE-2021-23954 is classified as a high severity vulnerability due to potential memory corruption and crash exploitation.

2

How do I fix CVE-2021-23954?

To fix CVE-2021-23954, update your software to Mozilla Thunderbird version 78.7 or higher, Mozilla Firefox version 85 or higher, or Mozilla Firefox ESR version 78.7 or higher.

3

What software is affected by CVE-2021-23954?

CVE-2021-23954 affects Mozilla Thunderbird versions up to 78.7, Mozilla Firefox versions up to 85, and Mozilla Firefox ESR versions up to 78.7.

4

What type of vulnerability is CVE-2021-23954?

CVE-2021-23954 is a type confusion vulnerability that could result in memory corruption.

5

What can happen if I don't address CVE-2021-23954?

If CVE-2021-23954 is not addressed, it may lead to crashes or potential exploitation of the affected software.

Contact

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