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.
Advisories
Source ID Title
Github GHSA Github GHSA GHSA-768j-98cg-p3fv fontTools is Vulnerable to Arbitrary File Write and XML injection in fontTools.varLib
Fixes

Solution

No solution given by the vendor.


Workaround

No workaround given by the vendor.

History

Mon, 01 Dec 2025 15:30:00 +0000

Type Values Removed Values Added
First Time appeared Fonttools
Fonttools fonttools
Vendors & Products Fonttools
Fonttools fonttools

Mon, 01 Dec 2025 14:15:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'poc', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Sat, 29 Nov 2025 01:15:00 +0000

Type Values Removed Values Added
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.
Title fontTools is Vulnerable to Arbitrary File Write and XML injection in fontTools.varLib
Weaknesses CWE-91
References
Metrics cvssV3_1

{'score': 6.3, 'vector': 'CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:C/C:N/I:H/A:L'}


cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2025-12-01T14:11:17.657Z

Reserved: 2025-11-21T01:08:02.615Z

Link: CVE-2025-66034

cve-icon Vulnrichment

Updated: 2025-12-01T13:56:43.840Z

cve-icon NVD

Status : Awaiting Analysis

Published: 2025-11-29T01:16:02.967

Modified: 2025-12-01T15:39:33.110

Link: CVE-2025-66034

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2025-12-01T15:18:18Z