CVE-2020-12406

Description

Mozilla Developer Iain Ireland discovered a missing type check during unboxed objects removal, resulting in a crash. We presume that with enough effort that it could be exploited to run arbitrary code. This vulnerability affects Thunderbird < 68.9.0, Firefox < 77, and Firefox ESR < 68.9.

Category

8.8
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.34%
Vendor Advisory ubuntu.com Vendor Advisory mozilla.org Vendor Advisory mozilla.org Vendor Advisory mozilla.org Vendor Advisory mozilla.org
Affected: Mozilla Thunderbird
Affected: Mozilla Firefox
Affected: Mozilla Firefox ESR
Published at:
Updated at:

References

Link Tags
https://www.mozilla.org/security/advisories/mfsa2020-20/ vendor advisory
https://www.mozilla.org/security/advisories/mfsa2020-21/ vendor advisory
https://www.mozilla.org/security/advisories/mfsa2020-22/ vendor advisory
https://bugzilla.mozilla.org/show_bug.cgi?id=1639590 issue tracking vendor advisory
https://usn.ubuntu.com/4421-1/ third party advisory vendor advisory

Frequently Asked Questions

What is the severity of CVE-2020-12406?
CVE-2020-12406 has been scored as a high severity vulnerability.
How to fix CVE-2020-12406?
To fix CVE-2020-12406, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2020-12406 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2020-12406 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2020-12406?
CVE-2020-12406 affects Mozilla Thunderbird, Mozilla Firefox, Mozilla Firefox ESR.
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