VULNERABILITY INTELLIGENCE
CVE-2021-38506
CVSS score4.3 MEDIUM
EPSS probability1.51%
CISA KEVNot currently listed
Published2021-12-08
Last modified2026-06-17
CVSS vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N
Description
Through a series of navigations, Firefox could have entered fullscreen mode without notification or warning to the user. This could lead to spoofing attacks on the browser UI including phishing. This vulnerability affects Firefox < 94, Thunderbird < 91.3, and Firefox ESR < 91.3.
Weakness classification
- nvd@nist.gov: CWE-1021
Primary references
- security@mozilla.org — Issue Tracking, Permissions Required, Vendor Advisory
- security@mozilla.org — Mailing List, Third Party Advisory
- security@mozilla.org — Mailing List, Third Party Advisory
- security@mozilla.org — Third Party Advisory
- security@mozilla.org — Third Party Advisory
- security@mozilla.org — Third Party Advisory
- security@mozilla.org — Third Party Advisory
- security@mozilla.org — Vendor Advisory
- security@mozilla.org — Vendor Advisory
- security@mozilla.org — Vendor Advisory
- af854a3a-2127-422b-91ae-364da2661108 — Issue Tracking, Permissions Required, Vendor Advisory
- af854a3a-2127-422b-91ae-364da2661108 — Mailing List, Third Party Advisory