CVE-2026-84127: Vulnerability in Mozilla Firefox
Description
Information disclosure in the WebExtensions component in Firefox for Android. This vulnerability was fixed in Firefox 155.
CVSS v3.1
Score 4.3medium
Affected software
Mozilla
Firefox
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-84127 is an information disclosure vulnerability affecting the WebExtensions component in Firefox for Android. The flaw could allow an attacker to gain access to information that should be protected. Mozilla fixed this vulnerability in Firefox 155. The CVSS v3.1 base score is 4.3 (medium), with vector AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N, indicating network attack vector, low attack complexity, no privileges required, user interaction required, unchanged scope, and limited confidentiality impact. No active exploitation has been reported. The vendor advisory confirms the fix in Firefox 155.
Potential Impact
The vulnerability allows unauthorized information disclosure in Firefox for Android's WebExtensions component. It does not affect integrity or availability. The impact is limited to confidentiality with a medium severity rating. There are no known exploits in the wild, reducing immediate risk.
Mitigation Recommendations
Mozilla fixed this vulnerability in Firefox 155. Users and administrators should update Firefox for Android to version 155 or later to remediate this issue. No additional mitigation actions are indicated by the vendor advisory.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-09-01T07:25:25.784Z
- State
- PUBLISHED
- Vendor Advisory Urls
- [{"url":"https://www.mozilla.org/security/advisories/mfsa2026-82/","vendor":"Mozilla"}]
Threat ID: 6a96cab0acd9273b49b6854e
Added to database: 09/01/2026, 12:53:04 UTC
Last enriched: 09/07/2026, 14:50:16 UTC
Last updated: 10/17/2026, 06:48:21 UTC
Views: 56
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