vulnerability
MFSA2025-51 Firefox: Security Vulnerabilities fixed in Firefox 140 (CVE-2025-6434)
| Severity | CVSS | Published | Added | Modified |
|---|---|---|---|---|
| 4 | (AV:N/AC:M/Au:N/C:N/I:P/A:N) | Jun 24, 2025 | Jun 25, 2025 | Apr 15, 2026 |
Severity
4
CVSS
(AV:N/AC:M/Au:N/C:N/I:P/A:N)
Published
Jun 24, 2025
Added
Jun 25, 2025
Modified
Apr 15, 2026
Description
The exception page for the HTTPS-Only feature, displayed when a website is opened via HTTP, lacked an anti-clickjacking delay, potentially allowing an attacker to trick a user into granting an exception and loading a webpage over HTTP. This vulnerability was fixed in Firefox 140 and Thunderbird 140.
Solution
mozilla-firefox-upgrade-140_0
Rapid7 Labs
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