CVE-2025-66034
Publication date 29 November 2025
Last updated 3 December 2025
Ubuntu priority
Description
fontTools is a library for manipulating fonts, written in Python. In versions from 4.33.0 to before 4.60.2, the fonttools varLib (or python3 -m fontTools.varLib) script has an arbitrary file write vulnerability that leads to remote code execution when a malicious .designspace file is processed. The vulnerability affects the main() code path of fontTools.varLib, used by the fonttools varLib CLI and any code that invokes fontTools.varLib.main(). This issue has been patched in version 4.60.2.
Status
| Package | Ubuntu Release | Status |
|---|---|---|
| fonttools | 25.10 questing |
Needs evaluation
|
| 25.04 plucky |
Needs evaluation
|
|
| 24.04 LTS noble |
Needs evaluation
|
|
| 22.04 LTS jammy |
Needs evaluation
|
|
| 20.04 LTS focal |
Needs evaluation
|
|
| 18.04 LTS bionic |
Needs evaluation
|
|
| 16.04 LTS xenial |
Needs evaluation
|
Severity score breakdown
| Parameter | Value |
|---|---|
| Base score |
6.3 · Medium
|
| Attack vector | Local |
| Attack complexity | High |
| Privileges required | None |
| User interaction | Required |
| Scope | Changed |
| Confidentiality | None |
| Integrity impact | High |
| Availability impact | Low |
| Vector | CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:C/C:N/I:H/A:L |