Vulnerability in Mozilla Firefox
CVE-2020-26953
It was possible to cause the browser to enter fullscreen mode without displaying the security UI; thus making it possible to attempt a phishing attack or otherwise confuse the user. This vulnerability affects Firefox < 83, Firefox ESR < 78.5, and Thunderbird < 78.5.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 4.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N.
EPSS exploit prediction
EPSS: 0.013 (69.2th percentile), scored .
Low probability of exploitation in the next 30 days, but still tracked. 69th percentile — 69.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.013 · newest: 0.013 · change: +0.000
Affected products
- Mozilla Firefox — versions < 83
- Mozilla Firefox Esr — versions < 78.5
- Mozilla Firefox Esr
- Mozilla Thunderbird — versions < 78.5
Weakness classification (CWE)
References
- bugzilla.mozilla.org/show_bug.cgi (Permissions Required, Issue Tracking, Vendor Advisory)
- www.mozilla.org/security/advisories/mfsa2020-50/ (Vendor Advisory)
- www.mozilla.org/security/advisories/mfsa2020-52/ (Vendor Advisory)
- www.mozilla.org/security/advisories/mfsa2020-51/ (Vendor Advisory)
Frequently asked questions
- What is CVE-2020-26953?
- CVE-2020-26953 is a medium-severity vulnerability in Mozilla Firefox, classified under Improper Restriction of Rendered UI Layers or Frames (Clickjacking). CVSS score: 4.3/10. Published 2020-12-09.
- How severe is CVE-2020-26953?
- Medium severity. CVSS v3 base score is 4.3 out of 10.