CVE-2026-100787
Received Received - Intake

XUL Sandbox Escape in Firefox ESR and Firefox

Publication date: 2026-09-29

Last updated on: 2026-09-29

Assigner: Mozilla Corporation

Description
Sandbox escape in the XUL component. This vulnerability was fixed in Firefox ESR 153.4 and Firefox 157.

CVSS Scores

EPSS Scores

Probability:
Percentile:

Meta Information

Published
2026-09-29
Last Modified
2026-09-29
Generated
2026-09-29
AI Q&A
2026-09-29
EPSS Evaluated
N/A
NVD
CVE-2026-100787
EUVD
EUVD-2026-88939

Affected Vendors & Products

Showing 4 associated CPEs
Vendor Product Version / Range
mozilla firefox to 153.4 (inc)
mozilla firefox to 157 (inc)
mozilla firefox 153.4
mozilla firefox 157

Helpful Resources

Exploitability

CWE
CWE Icon
KEV
KEV Icon
CWE ID Description
CWE-UNKNOWN

Attack-Flow Graph

AI Quick Actions

Instant insights powered by AI
Executive Summary

This is a sandbox escape vulnerability in the XUL component of Firefox. It allows malicious code to break out of the browser's security sandbox, potentially gaining unauthorized access to the host system.

Impact Analysis

If exploited, this vulnerability could allow attackers to execute arbitrary code on your system with the same privileges as your user account. This could lead to data theft, malware installation, or unauthorized system access.

Mitigation Strategies

Update Firefox ESR to version 153.4 or Firefox to version 157 or later to address the sandbox escape vulnerability in the XUL component.

Chat Assistant

Ask questions about this CVE
Hi! I’m here to help you understand CVE-2026-100787. Ask me anything about the vulnerability, its impact, or mitigation strategies.
0/70

EPSS Chart