Improper Certificate Validation in Mozilla Firefox and Firefox ESR - CVE-2020-12421
Published: July 2, 2020 / Updated: July 31, 2020
Vulnerability identifier: #VU29457
CSH Severity: Low
CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear
CVE-ID: CVE-2020-12421
CWE-ID: CWE-295
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vendor: Mozilla
Affected software:
Mozilla Firefox
Firefox ESR
Mozilla Firefox
Firefox ESR
Detailed vulnerability description
The vulnerability allows a remote attacker to disable installed Add-Ons.
The vulnerability exists due to Add-On updates do not respect the same certificate trust rules as software updates. 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 This could have caused add-ons to become out-of-date silently without notification to the user.
How to mitigate CVE-2020-12421
Install updates from vendor's website.