CVE-2025-6434
Publication date 24 June 2025
Last updated 13 May 2026
Ubuntu priority
Cvss 3 Severity Score
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.
Status
| Package | Ubuntu Release | Status |
|---|---|---|
| firefox | 26.04 LTS resolute |
Not affected
|
| 25.10 questing |
Not affected
|
|
| 24.04 LTS noble |
Not affected
|
|
| 22.04 LTS jammy |
Not affected
|
|
| mozjs102 | 26.04 LTS resolute | Not in release |
| 25.10 questing | Not in release | |
| 24.04 LTS noble | Ignored | |
| 22.04 LTS jammy | Ignored | |
| mozjs115 | 26.04 LTS resolute | Not in release |
| 25.10 questing | Not in release | |
| 24.04 LTS noble | Ignored | |
| 22.04 LTS jammy | Not in release | |
| mozjs38 | 26.04 LTS resolute | Not in release |
| 25.10 questing | Not in release | |
| 24.04 LTS noble | Not in release | |
| 22.04 LTS jammy | Not in release | |
| 18.04 LTS bionic |
Needs evaluation
|
|
| mozjs52 | 26.04 LTS resolute | Not in release |
| 25.10 questing | Not in release | |
| 24.04 LTS noble | Not in release | |
| 22.04 LTS jammy | Not in release | |
| 20.04 LTS focal | Ignored | |
| 18.04 LTS bionic | Ignored | |
| mozjs68 | 26.04 LTS resolute | Not in release |
| 25.10 questing | Not in release | |
| 24.04 LTS noble | Not in release | |
| 22.04 LTS jammy | Not in release | |
| 20.04 LTS focal | Ignored | |
| mozjs78 | 26.04 LTS resolute | Not in release |
| 25.10 questing | Not in release | |
| 24.04 LTS noble | Not in release | |
| 22.04 LTS jammy | Ignored | |
| mozjs91 | 26.04 LTS resolute | Not in release |
| 25.10 questing | Not in release | |
| 24.04 LTS noble | Not in release | |
| 22.04 LTS jammy | Ignored | |
| thunderbird | 26.04 LTS resolute |
Not affected
|
| 25.10 questing |
Not affected
|
|
| 24.04 LTS noble |
Not affected
|
|
| 22.04 LTS jammy |
Fixed 1:140.7.1+build1-0ubuntu0.22.04.1
|
Notes
mdeslaur
mozjs* contain a copy of the SpiderMonkey JavaScript engine. It is not feasible to backport security fixes to the mozjs* packages, as such, marking them as ignored. starting with Ubuntu 22.04, the firefox package is just a script that installs the Firefox snap starting with Ubuntu 24.04, the thunderbird package is just a script that installs the Thunderbird snap
Severity score breakdown
CVSS version: CVSS v3.0
Base score
4.3 · Medium
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N
References
Related Ubuntu Security Notices (USN)
- USN-7991-1
- Thunderbird vulnerabilities
- 2 February 2026