CVE-2025-10529

MEDIUM

Mozilla Firefox < 140.3.0 - Permissive CORS Policy

Title source: rule

Description

Same-origin policy bypass in the Layout component. This vulnerability was fixed in Firefox 143, Firefox ESR 140.3, Thunderbird 143, and Thunderbird 140.3.

References (7)

[Mailing List] https://lists.debian.org/debian-lts-announce/2025/09/msg00020.html

[Mailing List] https://lists.debian.org/debian-lts-announce/2025/09/msg00026.html

[Permissions Required] https://bugzilla.mozilla.org/show_bug.cgi?id=1970490

[Vendor Advisory] https://www.mozilla.org/security/advisories/mfsa2025-73/

[Vendor Advisory] https://www.mozilla.org/security/advisories/mfsa2025-75/

[Vendor Advisory] https://www.mozilla.org/security/advisories/mfsa2025-77/

[Vendor Advisory] https://www.mozilla.org/security/advisories/mfsa2025-78/

Scores

CVSS v3 6.5

EPSS 0.0006

EPSS Percentile 18.5%

Attack Vector NETWORK

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N

CISA SSVC

Vulnrichment

Exploitation none

Automatable yes

Technical Impact partial

Details

CWE

CWE-942

Status published

Products (7)

mozilla/firefox < 140.3.0

mozilla/firefox < 143.0

Mozilla/Firefox 140.3 - 140.*

Mozilla/Firefox 143

mozilla/thunderbird < 143.0

Mozilla/Thunderbird 140.3 - 140.*

Mozilla/Thunderbird 143

Published Sep 16, 2025

Tracked Since Feb 18, 2026