CVE-2020-12421

Description

When performing add-on updates, certificate chains terminating in non-built-in-roots were rejected (even if they were legitimately added by an administrator.) This could have caused add-ons to become out-of-date silently without notification to the user. This vulnerability affects Firefox ESR < 68.10, Firefox < 78, and Thunderbird < 68.10.0.

Category

6.5
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 1.00% Top 25%
Vendor Advisory opensuse.org Vendor Advisory opensuse.org Vendor Advisory opensuse.org Vendor Advisory opensuse.org Vendor Advisory ubuntu.com Vendor Advisory gentoo.org Vendor Advisory gentoo.org Vendor Advisory mozilla.org Vendor Advisory mozilla.org Vendor Advisory mozilla.org Vendor Advisory mozilla.org
Affected: Mozilla Firefox ESR
Affected: Mozilla Firefox
Affected: Mozilla Thunderbird
Published at:
Updated at:

References

Link Tags
https://www.mozilla.org/security/advisories/mfsa2020-24/ vendor advisory
https://www.mozilla.org/security/advisories/mfsa2020-26/ vendor advisory
https://www.mozilla.org/security/advisories/mfsa2020-25/ vendor advisory
https://bugzilla.mozilla.org/show_bug.cgi?id=1308251 vendor advisory issue tracking
http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00023.html vendor advisory broken link
http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00026.html vendor advisory broken link
http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00027.html vendor advisory broken link
http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00049.html vendor advisory broken link
https://usn.ubuntu.com/4421-1/ third party advisory vendor advisory
https://security.gentoo.org/glsa/202007-09 third party advisory vendor advisory
https://security.gentoo.org/glsa/202007-10 third party advisory vendor advisory

Frequently Asked Questions

What is the severity of CVE-2020-12421?
CVE-2020-12421 has been scored as a medium severity vulnerability.
How to fix CVE-2020-12421?
To fix CVE-2020-12421, 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-2020-12421 being actively exploited in the wild?
It is possible that CVE-2020-12421 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2020-12421?
CVE-2020-12421 affects Mozilla Firefox ESR, Mozilla Firefox, Mozilla Thunderbird.
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