Mozilla Firefox and Thunderbird Sandbox Escape Vulnerability in IndexedDB Component

Vulnerability

A sandbox escape vulnerability has been identified in the Storage: IndexedDB component, affecting multiple Mozilla products. This vulnerability is present in Firefox versions prior to 148, Firefox ESR versions prior to 140.8, Thunderbird versions prior to 148, and Thunderbird ESR versions prior to 140.8. The issue arises from incorrect boundary conditions, which can be exploited to escape the sandbox environment.

Impact

Exploitation of this vulnerability allows for a sandbox escape, potentially leading to unauthorized access or actions outside the intended security boundaries.

Remediation

Users can upgrade to Firefox 148, Firefox ESR 140.8, Thunderbird 148, or Thunderbird ESR 140.8 to address this vulnerability.

Added: Feb 24, 2026, 2:51 PM
Updated: Feb 24, 2026, 10:55 PM

Vulnerability Rating

Custom Algorithm
spread
8.4
impact
2.5
exploitability
4.4
remediation
7.7
relevance
3.1
threat
0.0
urgency
2.9
incentive
0.0

Our algorithm analyzes dozens of metrics to generate these 8 key vulnerability categories, which are then combined to calculate the overall risk score.