CVE-2026-84125
Received Received - Intake

Use-after-free in Firefox DOM Core & HTML

Publication date: 2026-09-01

Last updated on: 2026-09-01

Assigner: Mozilla Corporation

Description
Use-after-free in the DOM: Core & HTML component. This vulnerability was fixed in Firefox 155 and Firefox ESR 153.2.

CVSS Scores

EPSS Scores

Probability:
Percentile:

Meta Information

Published
2026-09-01
Last Modified
2026-09-01
Generated
2026-09-01
AI Q&A
2026-09-01
EPSS Evaluated
N/A
NVD
CVE-2026-84125
EUVD
EUVD-2026-69074

Affected Vendors & Products

Showing 4 associated CPEs
Vendor Product Version / Range
mozilla firefox 155
mozilla firefox_esr 153.2
mozilla firefox to 155 (inc)
mozilla firefox_esr to 153.2 (inc)

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 use-after-free vulnerability in Firefox's DOM: Core & HTML component. It occurs when a program tries to use memory after it has been freed, potentially leading to crashes or arbitrary code execution.

Detection Guidance

Detection requires checking Firefox version. Run 'firefox --version' or check 'about:support' in Firefox. Versions before 155 or Firefox ESR before 153.2 are vulnerable.

Impact Analysis

An attacker could exploit this to crash your browser or run malicious code on your system. It may allow unauthorized access to sensitive data or system resources if not patched.

Mitigation Strategies

Update Firefox to version 155 or later and Firefox ESR to 153.2 or later. Disable automatic updates temporarily if needed until patches are applied.

Chat Assistant

Ask questions about this CVE
Hi! I’m here to help you understand CVE-2026-84125. Ask me anything about the vulnerability, its impact, or mitigation strategies.
0/70

EPSS Chart