CVE-2021-23961: High severity thunderbird vulnerability

Published Jan 26, 2021
·
Updated

Further techniques that built on the slipstream research combined with a malicious webpage could have exposed both an internal network's hosts as well as services running on the user's local machine.

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<78.10
78.10
Mozilla Firefox<85
85
Mozilla Firefox ESR<78.10
78.10
Mozilla Firefox<85.0
Debian Debian Linux=9.0
Debian Debian Linux=10.0

Event History

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

Parent advisories

This vulnerability appears in the following advisories.

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Frequently Asked Questions

1

What is CVE-2021-23961?

CVE-2021-23961 refers to a vulnerability that could expose both an internal network's hosts and services running on the user's local machine.

2

Which software are affected by CVE-2021-23961?

Mozilla Thunderbird (up to version 78.10), Mozilla Firefox (up to version 85), and Mozilla Firefox ESR (up to version 78.10) are affected by CVE-2021-23961.

3

What is the severity level of CVE-2021-23961?

CVE-2021-23961 has a severity level of medium.

4

How can I fix CVE-2021-23961?

Ensure that you have updated Mozilla Thunderbird, Mozilla Firefox, and Mozilla Firefox ESR to the latest versions available, as specified in the remedy section.

5

Where can I find more information about CVE-2021-23961?

You can refer to the following references for more information about CVE-2021-23961: [Bugzilla](https://bugzilla.mozilla.org/show_bug.cgi?id=1677940), [Mozilla Security Advisories](https://www.mozilla.org/en-US/security/advisories/mfsa2021-14/), and [Mozilla Security Advisories](https://www.mozilla.org/en-US/security/advisories/mfsa2021-03/).

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