CVE-2025-10531
Publication date 16 September 2025
Last updated 3 February 2026
Ubuntu priority
Description
Mitigation bypass in the Web Compatibility: Tooling component. This vulnerability affects Firefox < 143 and Thunderbird < 143.
Status
| Package | Ubuntu Release | Status |
|---|---|---|
| firefox | 25.10 questing |
Not affected
|
| 24.04 LTS noble |
Not affected
|
|
| 22.04 LTS jammy |
Not affected
|
|
| thunderbird | 25.10 questing |
Not affected
|
| 24.04 LTS noble |
Not affected
|
|
| 22.04 LTS jammy |
Not affected
|
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
| Parameter | Value |
|---|---|
| Base score |
5.4 · Medium
|
| Attack vector | Network |
| Attack complexity | Low |
| Privileges required | None |
| User interaction | Required |
| Scope | Unchanged |
| Confidentiality | Low |
| Integrity impact | Low |
| Availability impact | None |
| Vector | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N |