VulnerabilityModified
CVE-2021-23984
A malicious extension could have opened a popup window lacking an address bar.
MEDIUM 6.5EPSS 1.11%
Does this matter?
Lower severity and a low EPSS score (1.11%). Track it; it rarely justifies an emergency change on its own.
Description
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.
- CVSS 3.1
- 6.5 MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N
- EPSS
- 1.11% probability · 64th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-290
- Affected
- mozilla/firefox · mozilla/firefox esr · mozilla/thunderbird
- Source
- security@mozilla.org
References
- https://bugzilla.mozilla.org/show_bug.cgi?id=1693664Issue Tracking, Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2021-10/Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2021-11/Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2021-12/Vendor Advisory
- https://bugzilla.mozilla.org/show_bug.cgi?id=1693664Issue Tracking, Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2021-10/Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2021-11/Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2021-12/Vendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.