CVE-2021-29967: High severity Mozilla Thunderbird vulnerability

Published Jun 1, 2021
·
Updated

Mozilla developers Christian Holler, Anny Gakhokidze, Alexandru Michis, Gabriele Svelto reported memory safety bugs present in Firefox 88 and Firefox ESR 78.11. 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 Gabriele Svelto, Anny Gakhokidze, Alexandru Michis, Christian Holler reported memory safety bugs present in Firefox 88 and Firefox ESR 78.10. 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 Gabriele Svelto, Anny Gakhokidze, Alexandru Michis, Christian Holler reported memory safety bugs present in Thunderbird 78.11. 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

Mozilla developers reported memory safety bugs present in Firefox 88 and Firefox ESR 78.11. 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 < 78.11, Firefox < 89, and Firefox ESR < 78.11.

Affected Software

45 affected componentsFixes available
Mozilla Thunderbird<78.11
78.11
Mozilla Firefox<89.0
Mozilla Firefox ESR<78.11
Mozilla Thunderbird<78.11
Mozilla Firefox<89
89
Mozilla Firefox ESR<78.11
78.11
alpine/firefox<89.0-r0
89.0-r0
alpine/firefox<89.0-r0
89.0-r0
alpine/firefox<89.0-r0
89.0-r0
alpine/firefox<89.0-r0
89.0-r0
alpine/firefox<89.0-r0
89.0-r0
alpine/firefox<89.0-r0
89.0-r0
alpine/firefox<89.0-r0
89.0-r0
alpine/firefox<89.0-r0
89.0-r0
alpine/firefox<89.0-r0
89.0-r0
alpine/firefox<89.0-r0
89.0-r0
alpine/firefox<89.0-r0
89.0-r0
alpine/firefox-esr<78.11.0-r0
78.11.0-r0
alpine/firefox-esr<78.11.0-r0
78.11.0-r0
alpine/firefox-esr<78.11.0-r0
78.11.0-r0
alpine/firefox-esr<78.11.0-r0
78.11.0-r0
alpine/firefox-esr<78.11.0-r0
78.11.0-r0
alpine/firefox-esr<78.11.0-r0
78.11.0-r0
alpine/firefox-esr<78.11.0-r0
78.11.0-r0
alpine/firefox-esr<78.11.0-r0
78.11.0-r0
alpine/firefox-esr<78.11.0-r0
78.11.0-r0
alpine/firefox-esr<78.11.0-r0
78.11.0-r0
alpine/firefox-esr<78.11.0-r0
78.11.0-r0
alpine/firefox-esr<78.11.0-r0
78.11.0-r0
alpine/librewolf<89.0-r0
89.0-r0
alpine/librewolf<89.0-r0
89.0-r0
alpine/librewolf<89.0-r0
89.0-r0
alpine/librewolf<89.0-r0
89.0-r0
alpine/mozjs78<78.12.0-r0
78.12.0-r0
alpine/mozjs78<78.12.0-r0
78.12.0-r0
alpine/mozjs78<78.12.0-r0
78.12.0-r0
alpine/mozjs78<78.12.0-r0
78.12.0-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 Thunderbird to a version that resolves this vulnerability.

    Fixed in 78.11
  2. Upgrade

    Upgrade Firefox to a version that resolves this vulnerability.

    Fixed in 89
  3. Upgrade

    Upgrade Firefox ESR to a version that resolves this vulnerability.

    Fixed in 78.11
  4. Upgrade

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

    Fixed in 89.0-r0
  5. Upgrade

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

    Fixed in 78.11.0-r0
  6. Upgrade

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

    Fixed in 89.0-r0
  7. Upgrade

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

    Fixed in 78.12.0-r0
  8. Upgrade

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

    Fixed in 91.3.2-r0

Event History

Jun 1, 2021
CVE Published
12:00 AM
Jun 24, 2021
CVE Published
via MITRE·01:14 PM
Data Sourced
via MITRE·01:14 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-2021-29967?

The severity of CVE-2021-29967 is high with a severity value of 7.

2

Which software versions are affected by CVE-2021-29967?

Firefox 88, Firefox ESR 78.11, and Thunderbird 78.11 are affected by CVE-2021-29967.

3

What is the risk associated with CVE-2021-29967?

CVE-2021-29967 poses a risk of memory corruption and potential exploitation.

4

How can I fix the vulnerability CVE-2021-29967?

To fix CVE-2021-29967, update Firefox to version 89 or higher, or Firefox ESR to version 78.11 or higher.

5

Where can I find more information about CVE-2021-29967?

You can find more information about CVE-2021-29967 in the Mozilla Security Advisories: MFS…

Company

Resources

Contact

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