CVE-2021-23994: High severity Mozilla Thunderbird vulnerability

Published Apr 19, 2021
·
Updated

A WebGL framebuffer was not initialized early enough, resulting in memory corruption and an out of bound write.

Affected Software

44 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<88.0
Mozilla Firefox ESR<78.10
Mozilla Thunderbird<78.10
Mozilla Firefox<88
88
Mozilla Firefox ESR<78.10
78.10
alpine/firefox<88.0-r0
88.0-r0
alpine/firefox<88.0-r0
88.0-r0
alpine/firefox<88.0-r0
88.0-r0
alpine/firefox<88.0-r0
88.0-r0
alpine/firefox<88.0-r0
88.0-r0
alpine/firefox<88.0-r0
88.0-r0
alpine/firefox<88.0-r0
88.0-r0
alpine/firefox<88.0-r0
88.0-r0
alpine/firefox<88.0-r0
88.0-r0
alpine/firefox<88.0-r0
88.0-r0
alpine/firefox<88.0-r0
88.0-r0
alpine/firefox-esr<78.10.0-r0
78.10.0-r0
alpine/firefox-esr<78.10.0-r0
78.10.0-r0
alpine/firefox-esr<78.10.0-r0
78.10.0-r0
alpine/firefox-esr<78.10.0-r0
78.10.0-r0
alpine/firefox-esr<78.10.0-r0
78.10.0-r0
alpine/firefox-esr<78.10.0-r0
78.10.0-r0
alpine/firefox-esr<78.10.0-r0
78.10.0-r0
alpine/firefox-esr<78.10.0-r0
78.10.0-r0
alpine/firefox-esr<78.10.0-r0
78.10.0-r0
alpine/firefox-esr<78.10.0-r0
78.10.0-r0
alpine/firefox-esr<78.10.0-r0
78.10.0-r0
alpine/firefox-esr<78.10.0-r0
78.10.0-r0
alpine/librewolf<88.0-r0
88.0-r0
alpine/librewolf<88.0-r0
88.0-r0
alpine/librewolf<88.0-r0
88.0-r0
alpine/librewolf<88.0-r0
88.0-r0
alpine/thunderbird<91.3.2-r0
91.3.2-r0
alpine/thunderbird<91.3.2-r0
91.3.2-r0
alpine/thunderbird<91.3.2-r0
91.3.2-r0
alpine/thunderbird<91.3.2-r0
91.3.2-r0
alpine/thunderbird<91.3.2-r0
91.3.2-r0
alpine/thunderbird<91.3.2-r0
91.3.2-r0
alpine/thunderbird<91.3.2-r0
91.3.2-r0
alpine/thunderbird<91.3.2-r0
91.3.2-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 78.10
  5. Upgrade

    Upgrade Firefox to a version that resolves this vulnerability.

    Fixed in 88
  6. Upgrade

    Upgrade Firefox ESR to a version that resolves this vulnerability.

    Fixed in 78.10
  7. Upgrade

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

    Fixed in 88.0-r0
  8. Upgrade

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

    Fixed in 78.10.0-r0
  9. Upgrade

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

    Fixed in 88.0-r0
  10. Upgrade

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

    Fixed in 91.3.2-r0

Event History

Apr 19, 2021
CVE Published
12:00 AM
Jun 24, 2021
CVE Published
via MITRE·01:26 PM
Data Sourced
via MITRE·01:26 PM
DescriptionWeakness
Data Sourced
via NVD·02:15 PM
DescriptionSeverityWeaknessAffected Software
Data Sourced
via OSV·02:15 PM
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-2021-23994?

CVE-2021-23994 has a medium severity level due to the potential for memory corruption and out-of-bounds write issues.

2

How do I fix CVE-2021-23994?

To fix CVE-2021-23994, update Mozilla Thunderbird and Firefox ESR to version 78.10 or later.

3

What software is affected by CVE-2021-23994?

CVE-2021-23994 affects Mozilla Thunderbird versions earlier than 78.10 and Firefox ESR versions earlier than 78.10.

4

Can CVE-2021-23994 lead to exploitation?

Yes, CVE-2021-23994 can potentially lead to exploitation through memory corruption vulnerabilities.

5

Is there a specific version of Firefox that resolves CVE-2021-23994?

Yes, upgrading to Firefox version 88 or later will resolve CVE-2021-23994.

Company

Resources

Contact

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