Name: CVE-2026-84137: Origin Validation Error
Creator: Rapid7
Published: 2026-09-01T00:00:00.000Z
License: https://www.rapid7.com/legal/website-terms-of-use/
Keywords: CVE, CVE-2026-84137, CWE-451, CWE-346, CVSS 4.3, EPSS 0.00129

Spoofing issue in the DOM: Core & HTML component. This vulnerability was fixed in Firefox 155, Firefox ESR 153.2, Thunderbird 155, and Thunderbird 153.2.

CVSS Details

CVSS 3.1 Base Score: 4.3
CVSS 3.1 Vector: (CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N)

Covered by Rapid7

Product	Vendor Advisory	Solution File	Added	Published
Amazon_linux_2023	—	Upgrade firefox-debuginfoUpgrade firefoxUpgrade firefox-debugsource	Oct 13, 2026	Sep 1, 2026
Mfsa2026 82	—	Upgrade to Mozilla Firefox version 155.0Upgrade to the latest version of Mozilla Firefox	Sep 1, 2026	Sep 1, 2026
Mfsa2026 85	—	Upgrade to Mozilla Firefox ESR version 153.2Upgrade to the latest version of Mozilla Firefox	Sep 1, 2026	Sep 1, 2026
Mozilla Thunderbird	—	Upgrade to the latest version of Mozilla ThunderbirdUpgrade to Mozilla Thunderbird version 153.2	Sep 1, 2026	Sep 1, 2026

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CVSS Details

Covered by Rapid7

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