CVE-2021-38493: High severity Mozilla Firefox ESR vulnerability
Mozilla developers Gabriele Svelto and Tyson Smith reported memory safety bugs present in Firefox 91 and Firefox ESR 78.13. 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 reported memory safety bugs present in Firefox 91 and Firefox ESR 78.13. 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 ESR < 78.14, Thunderbird < 78.14, and Firefox < 92.
Mozilla developers Tyson Smith and Gabriele Svelto reported memory safety bugs present in Firefox 91 and Firefox ESR 78.13. 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 Tyson Smith and Gabriele Svelto reported memory safety bugs present in Thunderbird 78.13. 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
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
Firefox ESRto a version that resolves this vulnerability.Fixed in 78.14 - Upgrade
Upgrade
Thunderbirdto a version that resolves this vulnerability.Fixed in 78.14 - Upgrade
Upgrade
Firefoxto a version that resolves this vulnerability.Fixed in 92 - Upgrade
Upgrade
alpine/firefoxto a version that resolves this vulnerability.Fixed in 92.0.1-r0 - Upgrade
Upgrade
alpine/firefox-esrto a version that resolves this vulnerability.Fixed in 78.14.0-r0 - Upgrade
Upgrade
alpine/firefox-esrto a version that resolves this vulnerability.Fixed in 91.2.0-r0 - Upgrade
Upgrade
alpine/librewolfto a version that resolves this vulnerability.Fixed in 92.0.1-r0 - Upgrade
Upgrade
alpine/mozjs78to a version that resolves this vulnerability.Fixed in 78.14.0-r0 - Upgrade
Upgrade
alpine/thunderbirdto a version that resolves this vulnerability.Fixed in 91.3.2-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-2021-38493?
CVE-2021-38493 has a medium severity rating due to the potential for memory corruption leading to arbitrary code execution.
How do I fix CVE-2021-38493?
To fix CVE-2021-38493, update Firefox to version 92 or higher, or update Firefox ESR and Thunderbird to version 78.14.
Which versions of Firefox are affected by CVE-2021-38493?
CVE-2021-38493 affects Firefox versions up to 91, Firefox ESR versions up to 78.13, and Thunderbird versions up to 78.13.
Is CVE-2021-38493 exploitable?
Yes, with sufficient effort, the memory safety bugs related to CVE-2021-38493 could potentially be exploited to execute arbitrary code.
Who reported CVE-2021-38493?
CVE-2021-38493 was reported by Mozilla developers Gabriele Svelto and Tyson Smith.