CVE-2021-23954: High severity Mozilla 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

48 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
alpine/firefox<85.0-r0
85.0-r0
alpine/firefox<85.0-r0
85.0-r0
alpine/firefox<85.0-r0
85.0-r0
alpine/firefox<85.0-r0
85.0-r0
alpine/firefox<85.0-r0
85.0-r0
alpine/firefox<85.0-r0
85.0-r0
alpine/firefox<85.0-r0
85.0-r0
alpine/firefox<85.0-r0
85.0-r0
alpine/firefox<85.0-r0
85.0-r0
alpine/firefox<85.0-r0
85.0-r0
alpine/firefox<85.0-r0
85.0-r0
alpine/firefox-esr<78.7.0-r0
78.7.0-r0
alpine/firefox-esr<78.7.0-r0
78.7.0-r0
alpine/firefox-esr<78.7.0-r0
78.7.0-r0
alpine/firefox-esr<78.7.0-r0
78.7.0-r0
alpine/firefox-esr<78.7.0-r0
78.7.0-r0
alpine/firefox-esr<78.7.0-r0
78.7.0-r0
alpine/firefox-esr<78.7.0-r0
78.7.0-r0
alpine/firefox-esr<78.7.0-r0
78.7.0-r0
alpine/firefox-esr<78.7.0-r0
78.7.0-r0
alpine/firefox-esr<78.7.0-r0
78.7.0-r0
alpine/firefox-esr<78.7.0-r0
78.7.0-r0
alpine/firefox-esr<78.7.0-r0
78.7.0-r0
alpine/librewolf<85.0-r0
85.0-r0
alpine/librewolf<85.0-r0
85.0-r0
alpine/librewolf<85.0-r0
85.0-r0
alpine/librewolf<85.0-r0
85.0-r0
alpine/mozjs78<78.7.0-r0
78.7.0-r0
alpine/mozjs78<78.7.0-r0
78.7.0-r0
alpine/mozjs78<78.7.0-r0
78.7.0-r0
alpine/mozjs78<78.7.0-r0
78.7.0-r0
alpine/thunderbird<78.7.0-r0
78.7.0-r0
alpine/thunderbird<78.7.0-r0
78.7.0-r0
alpine/thunderbird<78.7.0-r0
78.7.0-r0
alpine/thunderbird<78.7.0-r0
78.7.0-r0
alpine/thunderbird<78.7.0-r0
78.7.0-r0
alpine/thunderbird<78.7.0-r0
78.7.0-r0
alpine/thunderbird<78.7.0-r0
78.7.0-r0
alpine/thunderbird<78.7.0-r0
78.7.0-r0

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade debian/firefox to a version that resolves this vulnerability.

    Fixed in 118.0.2-1
  2. Upgrade

    Upgrade debian/firefox-esr to a version that resolves this vulnerability.

    Fixed in 91.12.0esr-1~deb10u1Fixed in 115.3.1esr-1~deb10u1Fixed in 102.15.0esr-1~deb11u1Fixed in 115.3.1esr-1~deb11u1Fixed in 102.15.1esr-1~deb12u1Fixed in 115.3.0esr-1~deb12u1Fixed in 115.3.0esr-1
  3. Upgrade

    Upgrade debian/thunderbird to a version that resolves this vulnerability.

    Fixed in 1:91.12.0-1~deb10u1Fixed in 1:115.3.1-1~deb10u1Fixed in 1:102.13.1-1~deb11u1Fixed in 1:115.3.1-1~deb11u1Fixed in 1:102.15.1-1~deb12u1Fixed in 1:115.3.1-1~deb12u1Fixed in 1:115.3.1-1
  4. Upgrade

    Upgrade Thunderbird to a version that resolves this vulnerability.

    Fixed in 78.7
  5. Upgrade

    Upgrade Firefox to a version that resolves this vulnerability.

    Fixed in 85
  6. Upgrade

    Upgrade Firefox ESR to a version that resolves this vulnerability.

    Fixed in 78.7
  7. Upgrade

    Upgrade alpine/firefox to a version that resolves this vulnerability.

    Fixed in 85.0-r0
  8. Upgrade

    Upgrade alpine/firefox-esr to a version that resolves this vulnerability.

    Fixed in 78.7.0-r0
  9. Upgrade

    Upgrade alpine/librewolf to a version that resolves this vulnerability.

    Fixed in 85.0-r0
  10. Upgrade

    Upgrade alpine/mozjs78 to a version that resolves this vulnerability.

    Fixed in 78.7.0-r0
  11. Upgrade

    Upgrade alpine/thunderbird to a version that resolves this vulnerability.

    Fixed in 78.7.0-r0

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
Data Sourced
via NVD·03:15 AM
DescriptionSeverityWeaknessAffected Software
Data Sourced
via OSV·03:15 AM
DescriptionSeverityAffected Software

Parent advisories

This vulnerability appears in the following advisories.

Peer vulnerabilities

Found alongside the following vulnerabilities.

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.

Company

Resources

Contact

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