CVSS 3.1
6.5 mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:NCVE-2021-23984
Medium (6.5) in mozilla. EPSS 1.1% chance of exploitation in the next 30 days.
A malicious extension could have opened a popup window lacking an address bar. The title of the popup lacking an address bar should not be fully controllable, but in this situation was. This could have been used to spoof a website and attempt to trick the user into providing credentials. This vulnerability affects Firefox ESR < 78.9, Firefox < 87, and Thunderbird < 78.9.
Severity
- EPSS
- 1.1% chance of exploitation in the next 30 days; higher than 66% of CVEs (scores of 2026-11-01)
- CWE
- CWE-290
- Published
- Modified
- Record from
- the NVD, synced
Affected
- mozilla:firefox
- mozilla:firefox_esr
- mozilla:thunderbird