VULNERABILITY INTELLIGENCE
CVE-2021-29961
CVSS score4.3 MEDIUM
EPSS probability0.76%
CISA KEVNot currently listed
Published2021-06-24
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
When styling and rendering an oversized `<select>` element, Firefox did not apply correct clipping which allowed an attacker to paint over the user interface. This vulnerability affects Firefox < 89.
Weakness classification
- CWE-863: Incorrect Authorization
Primary references
- security@mozilla.org — Broken Link, Issue Tracking, Vendor Advisory
- security@mozilla.org — Third Party Advisory
- security@mozilla.org — Release Notes, Vendor Advisory
- af854a3a-2127-422b-91ae-364da2661108 — Broken Link, Issue Tracking, Vendor Advisory
- af854a3a-2127-422b-91ae-364da2661108 — Third Party Advisory
- af854a3a-2127-422b-91ae-364da2661108 — Release Notes, Vendor Advisory