VULNERABILITY INTELLIGENCE
CVE-2021-43538
CVSS score4.3 MEDIUM
EPSS probability1.24%
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
By misusing a race in our notification code, an attacker could have forcefully hidden the notification for pages that had received full screen and pointer lock access, which could have been used for spoofing attacks. This vulnerability affects Thunderbird < 91.4.0, Firefox ESR < 91.4.0, and Firefox < 95.
Weakness classification
- CWE-362: Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')
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