CVE-2021-23964: High severity Mozilla Thunderbird vulnerability
Mozilla developers Alexis Beingessner, Christian Holler, Andrew McCreight, Tyson Smith, Jon Coppeard, André Bargull, Jason Kratzer, Jesse Schwartzentruber, Steve Fink, Byron Campen reported memory safety bugs present in Firefox 84 and Firefox ESR 78.6. 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 Alexis Beingessner, Christian Holler, Andrew McCreight, Tyson Smith, Jon Coppeard, André Bargull, Jason Kratzer, Jesse Schwartzentruber, Steve Fink, Byron Campen reported memory safety bugs present in Thunderbird 78.6. 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 Andrew McCreight, Tyson Smith, Jesse Schwartzentruber, Jon Coppeard, Byron Campen, André Bargull, Steve Fink, Jason Kratzer, Christian Holler, Alexis Beingessner reported memory safety bugs present in Firefox 84 and Firefox ESR 78.6. 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 84 and Firefox ESR 78.6. 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 Firefox < 85, Thunderbird < 78.7, and Firefox ESR < 78.7.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
debian/firefoxto a version that resolves this vulnerability.Fixed in 118.0.2-1 - Upgrade
Upgrade
debian/firefox-esrto 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 - Upgrade
Upgrade
debian/thunderbirdto 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 - Upgrade
Upgrade
Thunderbirdto a version that resolves this vulnerability.Fixed in 78.7 - Upgrade
Upgrade
Firefoxto a version that resolves this vulnerability.Fixed in 85 - Upgrade
Upgrade
Firefox ESRto a version that resolves this vulnerability.Fixed in 78.7 - Upgrade
Upgrade
alpine/firefoxto a version that resolves this vulnerability.Fixed in 85.0-r0 - Upgrade
Upgrade
alpine/firefox-esrto a version that resolves this vulnerability.Fixed in 78.7.0-r0 - Upgrade
Upgrade
alpine/librewolfto a version that resolves this vulnerability.Fixed in 85.0-r0 - Upgrade
Upgrade
alpine/mozjs78to a version that resolves this vulnerability.Fixed in 78.7.0-r0 - Upgrade
Upgrade
alpine/thunderbirdto a version that resolves this vulnerability.Fixed in 78.7.0-r0
Event History
Parent advisories
This vulnerability appears in the following advisories.
Peer vulnerabilities
Found alongside the following vulnerabilities.
Frequently Asked Questions
What is the severity of CVE-2021-23964?
CVE-2021-23964 is a memory safety vulnerability that can potentially be exploited, requiring immediate attention.
How do I fix CVE-2021-23964?
To fix CVE-2021-23964, update your Mozilla Firefox to version 85 or Mozilla Thunderbird to version 78.7.
Which versions are affected by CVE-2021-23964?
CVE-2021-23964 affects Firefox versions prior to 85 and Thunderbird versions prior to 78.7.
Is there a workaround for CVE-2021-23964?
There are no known workarounds for CVE-2021-23964; updating to the latest versions is the recommended action.
Can CVE-2021-23964 cause data loss?
CVE-2021-23964 has the potential to lead to data corruption or loss if exploited.