Mozilla Firefox up to 84.x Pointer Lock clickjacking

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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5.1$0-$5k0.00

Summaryinfo

A vulnerability described as problematic has been identified in Mozilla Firefox up to 84.x. This vulnerability affects unknown code of the component Pointer Lock Handler. The manipulation results in clickjacking. This vulnerability was named CVE-2021-23955. The attack may be performed from remote. There is no available exploit. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability was found in Mozilla Firefox up to 84.x (Web Browser). It has been classified as problematic. Affected is an unknown code block of the component Pointer Lock Handler. The manipulation with an unknown input leads to a clickjacking vulnerability. CWE is classifying the issue as CWE-451. The user interface (UI) does not properly represent critical information to the user, allowing the information - or its source - to be obscured or spoofed. This is often a component in phishing attacks. This is going to have an impact on integrity.

The weakness was presented 02/26/2021. The advisory is shared for download at bugzilla.mozilla.org. This vulnerability is traded as CVE-2021-23955. Successful exploitation requires user interaction by the victim. There are neither technical details nor an exploit publicly available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 08/09/2025). The MITRE ATT&CK project declares the attack technique as T1566.003.

The vulnerability scanner Nessus provides a plugin with the ID 246650 (Linux Distros Unpatched Vulnerability : CVE-2021-23955), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 85.0 eliminates this vulnerability. The upgrade is hosted for download at mozilla.org.

The vulnerability is also documented in the vulnerability database at Tenable (246650). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.2
VulDB Meta Temp Score: 5.1

VulDB Base Score: 4.3
VulDB Temp Score: 4.1
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 6.1
NVD Vector: 🔍

CVSSv2info

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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍

Exploitinginfo

Class: Clickjacking
CWE: CWE-451
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 246650
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2021-23955

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: Firefox 85.0

Timelineinfo

01/13/2021 🔍
02/26/2021 +44 days 🔍
02/26/2021 +0 days 🔍
08/09/2025 +1625 days 🔍

Sourcesinfo

Vendor: mozilla.org
Product: mozilla.org

Advisory: bugzilla.mozilla.org
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2021-23955 (🔍)
GCVE (CVE): GCVE-0-2021-23955
GCVE (VulDB): GCVE-100-170448

Entryinfo

Created: 02/26/2021 09:32
Updated: 08/09/2025 18:00
Changes: 02/26/2021 09:32 (42), 03/05/2021 12:52 (5), 03/05/2021 12:55 (18), 08/09/2025 18:00 (17)
Complete: 🔍
Cache ID: 216::103

VulDB is the best source for vulnerability data and more expert information about this specific topic.

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