CVE-2026-0881
Publication date 13 January 2026
Last updated 3 February 2026
Ubuntu priority
Description
Sandbox escape in the Messaging System component. This vulnerability affects Firefox < 147 and Thunderbird < 147.
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 |
10.0 · Critical
|
| Attack vector | Network |
| Attack complexity | Low |
| Privileges required | None |
| User interaction | None |
| Scope | Changed |
| Confidentiality | High |
| Integrity impact | High |
| Availability impact | High |
| Vector | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H |