VDB-165801 · CVE-2020-26963 · mfsa2020-50

Mozilla Firefox up to 82.x API denial of service

CVSS Meta Temp Score CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.	Current Exploit Price (≈) Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.	CTI Interest Score Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
4.2	$0-$5k	0.00

Summaryinfo

A vulnerability classified as problematic has been found in Mozilla Firefox up to 82.x. This impacts an unknown function of the component API Handler. Performing a manipulation results in denial of service. This vulnerability is identified as CVE-2020-26963. The attack can be initiated remotely. There is not any exploit available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as problematic, was found in Mozilla Firefox up to 82.x (Web Browser). This affects some unknown processing of the component API Handler. The manipulation with an unknown input leads to a denial of service vulnerability. CWE is classifying the issue as CWE-404. The product does not release or incorrectly releases a resource before it is made available for re-use. This is going to have an impact on availability.

The weakness was released 12/09/2020 as mfsa2020-50. The advisory is shared at mozilla.org. This vulnerability is uniquely identified as CVE-2020-26963. It demands that the victim is doing some kind of user interaction. Neither technical details nor an exploit are publicly available. MITRE ATT&CK project uses the attack technique T1499 for this issue.

The vulnerability scanner Nessus provides a plugin with the ID 248459 (Linux Distros Unpatched Vulnerability : CVE-2020-26963), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 83.0 eliminates this vulnerability. The upgrade is hosted for download at mozilla.org.

The vulnerability is also documented in the vulnerability database at Tenable (248459). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Type

Web Browser

Vendor

Mozilla

Name

Firefox

Version

82.x

License

open-source

Website

Vendor: https://www.mozilla.org/
Product: https://www.mozilla.org/en-US/firefox/

CPE 2.3info

🔍

CPE 2.2info

🔍

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.3
VulDB Meta Temp Score: 4.2

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

NVD Base Score: 4.3
NVD Vector: 🔍

CVSSv2info

AV	AC	Au	C	I	A
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳

Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock

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

NVD Base Score: 🔍

Exploitinginfo

Class: Denial of service
CWE: CWE-404
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

0-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

Nessus ID: 248459
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2020-26963

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: Firefox 83.0

Timelineinfo

10/12/2020 🔍
12/09/2020 +58 days 🔍
12/09/2020 +0 days 🔍
08/12/2025 +1707 days 🔍

Sourcesinfo

Vendor: mozilla.org
Product: mozilla.org

Advisory: mfsa2020-50
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2020-26963 (🔍)
GCVE (CVE): GCVE-0-2020-26963
GCVE (VulDB): GCVE-100-165801

Entryinfo

Created: 12/09/2020 11:02
Updated: 08/12/2025 05:00
Changes: 12/09/2020 11:02 (42), 12/14/2020 09:25 (6), 12/14/2020 09:30 (16), 08/12/2025 05:00 (17)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.