CVE-2021-38500: High severity thunderbird vulnerability

Published Oct 5, 2021
·
Updated

Mozilla developers and community members Andreas Pehrson and Christian Holler reported memory safety bugs present in Firefox 92 and Firefox ESR 91.1. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code.

Other sources

Mozilla developers and community members Andreas Pehrson and Christian Holler reported memory safety bugs present in Thunderbird 91.1. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code.

Mozilla developers reported memory safety bugs present in Firefox 92 and Firefox ESR 91.1. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability affects Thunderbird < 78.15, Thunderbird < 91.2, Firefox ESR < 91.2, Firefox ESR < 78.15, and Firefox < 93.

Affected Software

16 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<91.2
91.2
Mozilla Firefox<93
93
Mozilla Firefox ESR<91.2
91.2
Mozilla Firefox ESR<78.15
78.15
Mozilla Firefox<93.0
Mozilla Firefox>=91.0<91.2
Mozilla Firefox ESR<78.15
Mozilla Thunderbird<78.15
Mozilla Thunderbird>=91.0<91.2
Debian Debian Linux=9.0
Debian Debian Linux=10.0
Debian Debian Linux=11.0
Mozilla Firefox ESR>=91.0<91.2

Event History

Oct 5, 2021
CVE Published
via Mozilla·12:00 AM
Nov 3, 2021
CVE Published
via MITRE·12:03 AM
Data Sourced
via MITRE·12:03 AM
DescriptionWeakness
Data Sourced
via NVD·01:15 AM
DescriptionSeverityAffected Software

Parent advisories

This vulnerability appears in the following advisories.

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Frequently Asked Questions

1

What is the vulnerability ID of this vulnerability?

The vulnerability ID is CVE-2021-38500.

2

What is the severity of CVE-2021-38500?

The severity of CVE-2021-38500 is high with a severity score of 8.8.

3

Which software is affected by CVE-2021-38500?

Firefox versions up to and excluding 93, Firefox ESR versions up to and excluding 78.15, and Thunderbird versions up to and excluding 78.15 are affected by CVE-2021-38500.

4

How can I fix CVE-2021-38500?

Updating to Firefox version 93, Firefox ESR version 78.15, or Thunderbird version 78.15 will fix CVE-2021-38500.

5

Where can I find more information about CVE-2021-38500?

You can find more information about CVE-2021-38500 at the following references: [Mozilla Bugzilla](https://bugzilla.mozilla.org/buglist.cgi?bug_id=1725854%2C1728321), [Mozilla Security Advisories](https://www.mozilla.org/en-US/security/advisories/mfsa2021-47/), [Debian LTS Announcement](https://lists.debian.org/debian-lts-announce/2022/01/msg00001.html).

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