Home/CVE/A malicious extension could have opened a popup window lacking an address bar. The title of the popup lacking an address
CVE

CVE-2021-23984

A malicious extension could have opened a popup window lacking an address bar. The title of the popup lacking an address

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.

MEDIUM · CVSS 6.5 EPSS 0.0029
Monitor
  • No active-exploitation, high-EPSS, or public-exploit signals - routine patching cadence
Sigma rules1 YARA rules0
⬡

Weakness Classification

CWE-290Authentication Bypass by Spoofing
▤

Affected Products & Versions

3
mozilla firefox< 87.0
mozilla firefox esr< 78.9
mozilla thunderbird< 78.9
◈

Sigma Hunt Rules

1
Exact rules name this CVE ID. Product rules name an affected product in their title. Related rules cover techniques used by actors who exploited this CVE. Showing the most relevant matches; the complete related set is on the full drill-down.
producthighSQLite Firefox Profile Data DB Access
▣

Scoring & Timeline

6.5
MEDIUM · CVSS v3.1 · security@mozilla.org
View on NVD
Attack Vector
Network Adjacent Local Physical
Attack Complexity
Low High
Privileges Required
None Low High
User Interaction
None Required
Scope
Unchanged Changed
Confidentiality
None Low High
Integrity
None Low High
Availability
None Low High
Published to NVD31 Mar 2021 · 02:15 PM
CVSS VectorCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N
⚑

Vendor Advisories

22
suse-csafopenSUSE-SU-2024:14572-1
suse-csafopenSUSE-SU-2024:10600-1
suse-csafopenSUSE-SU-2024:10601-1
usnUSN-4995-2
usnUSN-4995-1
🔗

References & Sources

4
Source URLs (vendor pages, mailing lists, write-ups). Exploit/PoC links are in their own section above to avoid duplication.
https://bugzilla.mozilla.org/show_bug.cgi?id=1693664Issue TrackingVendor 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
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