Vulnerability in Mozilla Firefox
CVE-2020-12421
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 This could have caused add-ons to become out-of-date silently without notification to the user.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.
Vulnerability class: Improper Certificate Validation
Published · last modified .
CVSS v3 metric
CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N.
EPSS exploit prediction
EPSS: 0.018 (78.2th percentile), scored .
Low probability of exploitation in the next 30 days, but still tracked. 78th percentile — 78.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.018 · newest: 0.018 · change: 0.000
Affected products
- Mozilla Firefox — versions unspecified
- Mozilla Firefox Esr — versions unspecified
- Mozilla Firefox Esr
- Mozilla Thunderbird — versions unspecified
- Canonical Ubuntu Linux — versions 16.04, 18.04, 19.10
Weakness classification (CWE)
References
- www.mozilla.org/security/advisories/mfsa2020-24/ (Vendor Advisory)
- www.mozilla.org/security/advisories/mfsa2020-26/ (Vendor Advisory)
- www.mozilla.org/security/advisories/mfsa2020-25/ (Vendor Advisory)
- bugzilla.mozilla.org/show_bug.cgi (Issue Tracking, Vendor Advisory)
- lists.opensuse.org/opensuse-security-announce/2020-07/msg00023.html (vendor-advisory, Broken Link)
- lists.opensuse.org/opensuse-security-announce/2020-07/msg00026.html (vendor-advisory, Broken Link)
- lists.opensuse.org/opensuse-security-announce/2020-07/msg00027.html (vendor-advisory, Broken Link)
- lists.opensuse.org/opensuse-security-announce/2020-07/msg00049.html (vendor-advisory, Broken Link)
- usn.ubuntu.com/4421-1/ (vendor-advisory, Third Party Advisory)
- security.gentoo.org/glsa/202007-09 (vendor-advisory, Third Party Advisory)
Frequently asked questions
- What is CVE-2020-12421?
- CVE-2020-12421 is a medium-severity vulnerability in Mozilla Firefox, classified under Improper Certificate Validation. CVSS score: 6.5/10. Published 2020-07-09.
- How severe is CVE-2020-12421?
- Medium severity. CVSS v3 base score is 6.5 out of 10.