Mozilla Firefox And Thunderbird Use-After-Free Vulnerability

Technical Severity

CVSS v3.1 Metrics

HIGH

8.1 / 10

Minimal Risk Critical

Vector Specification

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

Exploitation Likelihood

EPSS Prediction

3.13 %

Predictive Probability

Percentile Rank

86.8 th

Documented as more likely to be exploited than 86.8% of known CVEs.

Detection Date

Nov 03, 2021

Remediation Due

May 03, 2022

CISA Catalog Active

Threat Analysis

Mozilla Firefox and Thunderbird contain a race condition vulnerability when handling a ReadableStream under certain conditions. The race condition creates a use-after-free vulnerability, causing unspecified impacts.

Remediation Directive

Apply updates per vendor instructions.

External Intelligence

NVD

National Vulnerability Database

https://nvd.nist.gov/vuln/detail/CVE-2020-6820