CVE-2026-74966: Vulnerability in Mozilla Firefox
CVE-2026-74966 is an information disclosure vulnerability in the Form Autofill component of Mozilla Firefox. This flaw could allow unauthorized access to sensitive autofill data. The issue was addressed and fixed in Firefox version 154 and Firefox ESR 153.1, as well as Thunderbird versions 154 and 153.1.
AI Analysis
Technical Summary
CVE-2026-74966 is an information disclosure vulnerability affecting the Form Autofill component in Mozilla Firefox. The vulnerability allows unauthorized disclosure of sensitive information handled by the autofill feature. Mozilla fixed this vulnerability in Firefox 154 and Firefox ESR 153.1. The CVSS v3.1 base score is 7.5, indicating a high severity with network attack vector, low attack complexity, no privileges required, and no user interaction needed. The vulnerability impacts confidentiality but does not affect integrity or availability.
Potential Impact
Successful exploitation of this vulnerability could lead to unauthorized disclosure of sensitive autofill data, potentially exposing user personal information. The impact is limited to confidentiality loss without affecting integrity or availability of the system.
Mitigation Recommendations
Mozilla has released official fixes for this vulnerability in Firefox 154 and Firefox ESR 153.1. Users and administrators should update affected Firefox and Thunderbird installations to these versions or later to remediate the issue. No additional mitigation actions are required beyond applying the official patches.
CVE-2026-74966: Vulnerability in Mozilla Firefox
Description
CVE-2026-74966 is an information disclosure vulnerability in the Form Autofill component of Mozilla Firefox. This flaw could allow unauthorized access to sensitive autofill data. The issue was addressed and fixed in Firefox version 154 and Firefox ESR 153.1, as well as Thunderbird versions 154 and 153.1.
CVSS v3.1
Score 7.5high
Affected software
Mozilla
Firefox
Mozilla
Thunderbird
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-74966 is an information disclosure vulnerability affecting the Form Autofill component in Mozilla Firefox. The vulnerability allows unauthorized disclosure of sensitive information handled by the autofill feature. Mozilla fixed this vulnerability in Firefox 154 and Firefox ESR 153.1. The CVSS v3.1 base score is 7.5, indicating a high severity with network attack vector, low attack complexity, no privileges required, and no user interaction needed. The vulnerability impacts confidentiality but does not affect integrity or availability.
Potential Impact
Successful exploitation of this vulnerability could lead to unauthorized disclosure of sensitive autofill data, potentially exposing user personal information. The impact is limited to confidentiality loss without affecting integrity or availability of the system.
Mitigation Recommendations
Mozilla has released official fixes for this vulnerability in Firefox 154 and Firefox ESR 153.1. Users and administrators should update affected Firefox and Thunderbird installations to these versions or later to remediate the issue. No additional mitigation actions are required beyond applying the official patches.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-08-17T11:58:35.525Z
- State
- PUBLISHED
- Vendor Advisory Urls
- [{"url":"https://www.mozilla.org/security/advisories/mfsa2026-74/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-77/","vendor":"Mozilla"}]
Threat ID: 6a845509c6e8be0332367441
Added to database: 08/18/2026, 12:50:17 UTC
Last enriched: 09/11/2026, 21:48:47 UTC
Last updated: 10/02/2026, 02:46:06 UTC
Views: 32
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