CVE-2021-23960: High severity thunderbird vulnerability

Published Jan 26, 2021
·
Updated

Performing garbage collection on re-declared JavaScript variables resulted in a user-after-poison, 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·02:05 AM
Data Sourced
via MITRE·02:05 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-2021-23960?

CVE-2021-23960 is classified as a high-severity vulnerability due to the potential for user-after-poison exploitation leading to a crash.

2

How do I fix CVE-2021-23960?

To resolve CVE-2021-23960, upgrade affected applications to versions newer than 78.7 for Thunderbird or 85 for Firefox.

3

Which software is affected by CVE-2021-23960?

CVE-2021-23960 affects Mozilla Thunderbird versions up to 78.7, Firefox versions up to 85, and Firefox ESR versions up to 78.7.

4

What is the impact of CVE-2021-23960 on users?

Users of vulnerable software may experience crashes and could be exposed to potential exploit scenarios due to unhandled JavaScript variables.

5

Is CVE-2021-23960 being actively exploited?

There have been reports suggesting that CVE-2021-23960 may be exploited in the wild, which emphasizes the importance of updating affected applications promptly.

Contact

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