CVE-2025-6434
HTTPS-Only exception screen lacked anti-clickjacking delay
- State
- Published
- Severity
- 4.3 Medium
- Published
- Jun 24, 2025
- Updated
- Apr 13, 2026
- Reserved
- Jun 20, 2025
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.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 3.1 | 4.3 Medium | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N | CISA-ADP |
Weaknesses
- CWE-1021 Improper Restriction of Rendered UI Layers or Frames
Affected Products
| Product | Versions |
|---|---|
FirefoxMozilla |
|
ThunderbirdMozilla |
|
References
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