CVE-2021-23984

Mozilla: Malicious extensions could have spoofed popup information

Severity Score

6.5

*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

*Multiple Sources

Exploited in Wild

*KEV

Decision

*SSVC

Descriptions

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.

Una extensión maliciosa podría haber abierto una ventana emergente sin una barra de direcciones. El título de la ventana emergente que carece de una barra de direcciones no debería ser totalmente controlable, pero en esta situación sí lo era. Esto podría haber sido usado para falsificar un sitio web e intentar engañar al usuario para que proporcione credenciales. Esta vulnerabilidad afecta a Firefox ESR versiones anteriores a 78.9, Firefox versiones anteriores a 87, and Thunderbird versiones anteriores a 78.9

The Mozilla Foundation Security Advisory describes this issue as:

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.

*Credits: N/A

CVSS Scores

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

Required

Scope

Unchanged

Confidentiality

None

Integrity

High

Availability

None

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

Required

Scope

Changed

Confidentiality

Low

Integrity

Low

Availability

None

Attack Vector

Network

Attack Complexity

Medium

Authentication

None

Confidentiality

None

Integrity

Partial

Availability

None

* Common Vulnerability Scoring System

SSVC

Decision:-

Exploitation

Automatable

Tech. Impact

* Organization's Worst-case Scenario

Timeline

2021-01-13 CVE Reserved
2021-03-25 CVE Published
2023-12-15 EPSS Updated
2024-08-03 CVE Updated
---------- Exploited in Wild
---------- KEV Due Date
---------- First Exploit

CWE

CWE-290: Authentication Bypass by Spoofing
CWE-1021: Improper Restriction of Rendered UI Layers or Frames

CAPEC

References (6)

URL	Tag	Source

URL	Date	SRC

URL	Date	SRC

URL	Date	SRC
https://bugzilla.mozilla.org/show_bug.cgi?id=1693664	2021-08-06
https://www.mozilla.org/security/advisories/mfsa2021-10	2021-08-06
https://www.mozilla.org/security/advisories/mfsa2021-11	2021-08-06
https://www.mozilla.org/security/advisories/mfsa2021-12	2021-08-06
https://access.redhat.com/security/cve/CVE-2021-23984	2021-03-25
https://bugzilla.redhat.com/show_bug.cgi?id=1942786	2021-03-25

Affected Vendors, Products, and Versions

Vendor		Product				Version		Other		Status
Vendor	Product	Version	Other	Status	<-- -->	Vendor	Product	Version	Other	Status
Mozilla Search vendor "Mozilla"		Firefox Search vendor "Mozilla" for product "Firefox"				< 87.0 Search vendor "Mozilla" for product "Firefox" and version " < 87.0"		-		Affected
Mozilla Search vendor "Mozilla"		Firefox Esr Search vendor "Mozilla" for product "Firefox Esr"				< 78.9 Search vendor "Mozilla" for product "Firefox Esr" and version " < 78.9"		-		Affected
Mozilla Search vendor "Mozilla"		Thunderbird Search vendor "Mozilla" for product "Thunderbird"				< 78.9 Search vendor "Mozilla" for product "Thunderbird" and version " < 78.9"		-		Affected