Mozilla Firefox up to 88.x SELECT Element ui layer

CVSS Meta Temp Score
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CTI Interest Score
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4.8$0-$5k0.00

Summaryinfo

A vulnerability classified as problematic has been found in Mozilla Firefox up to 88.x. This affects an unknown part of the component SELECT Element Handler. The manipulation leads to ui layer. This vulnerability is referenced as CVE-2021-29961. Remote exploitation of the attack is possible. No exploit is available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability was found in Mozilla Firefox up to 88.x (Web Browser) and classified as problematic. This issue affects some unknown processing of the component SELECT Element Handler. The manipulation with an unknown input leads to a ui layer vulnerability. Using CWE to declare the problem leads to CWE-1021. The web application does not restrict or incorrectly restricts frame objects or UI layers that belong to another application or domain, which can lead to user confusion about which interface the user is interacting with. Impacted is integrity, and availability.

The weakness was published 06/25/2021. It is possible to read the advisory at mozilla.org. The identification of this vulnerability is CVE-2021-29961. It demands that the victim is doing some kind of user interaction. The technical details are unknown and an exploit is not publicly available. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 08/17/2025).

The vulnerability scanner Nessus provides a plugin with the ID 250021 (Linux Distros Unpatched Vulnerability : CVE-2021-29961), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 89.0 eliminates this vulnerability. The upgrade is hosted for download at mozilla.org.

The vulnerability is also documented in the vulnerability database at Tenable (250021). Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.9
VulDB Meta Temp Score: 4.8

VulDB Base Score: 5.4
VulDB Temp Score: 5.2
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 4.3
NVD Vector: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍

Exploitinginfo

Class: Ui layer
CWE: CWE-1021
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: 250021
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2021-29961

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: Firefox 89.0

Timelineinfo

04/01/2021 🔍
06/25/2021 +85 days 🔍
06/25/2021 +0 days 🔍
08/17/2025 +1514 days 🔍

Sourcesinfo

Vendor: mozilla.org
Product: mozilla.org

Advisory: mozilla.org
Status: Confirmed

CVE: CVE-2021-29961 (🔍)
GCVE (CVE): GCVE-0-2021-29961
GCVE (VulDB): GCVE-100-177575

Entryinfo

Created: 06/25/2021 11:50
Updated: 08/17/2025 19:24
Changes: 06/25/2021 11:50 (40), 07/02/2021 11:30 (5), 07/02/2021 11:37 (18), 08/17/2025 19:24 (17)
Complete: 🔍
Cache ID: 216::103

Be aware that VulDB is the high quality source for vulnerability data.

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