CVE-2026-8961

Analyzed Analyzed - Analysis Complete

Spoofing in Firefox Form Autofill Component

Publication date: 2026-05-19

Last updated on: 2026-05-20

Assigner: Mozilla Corporation

Description

Spoofing issue in the Form Autofill component. This vulnerability was fixed in Firefox 151, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.

CVSS Scores

EPSS Scores

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Meta Information

Published

2026-05-19

Last Modified

2026-05-20

Generated

2026-06-30

AI Q&A

2026-05-19

EPSS Evaluated

2026-06-28

NVD

CVE-2026-8961

EUVD

EUVD-2026-30912

Affected Vendors & Products

Vendor	Product	Version / Range
mozilla	firefox	to 151.0.0 (exc)
mozilla	firefox	to 140.11.0 (exc)
mozilla	thunderbird	to 140.11 (exc)
mozilla	thunderbird	to 151.0.0 (exc)

Helpful Resources

Exploitability

CWE

KEV

CWE ID	Description
CWE-290	This attack-focused weakness is caused by incorrectly implemented authentication schemes that are subject to spoofing attacks.

Attack-Flow Graph

Executive Summary

This vulnerability is a spoofing issue found in the Form Autofill component of Mozilla Firefox. It allows an attacker to potentially deceive users by presenting false or misleading information in form fields.

The issue was addressed and fixed in Firefox version 151 and Firefox ESR 140.11.

Impact Analysis

The spoofing vulnerability in the Form Autofill component can lead to users being tricked into entering sensitive information into fraudulent form fields. This can result in unauthorized disclosure of personal or financial data.

Mitigation Strategies

To mitigate this vulnerability, update your Firefox browser to version 151 or later, or Firefox ESR to version 140.11 or later, where the issue has been fixed.

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