CVE-2025-66034

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.

CVSS v3 6.3 MEDIUM

6.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.0 / Impact : 4.7

Attack Vector LOCAL

Attack Complexity HIGH

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact NONE

Integrity Impact HIGH

Availability Impact LOW

Scope CHANGED

References

Link	Resource
https://github.com/fonttools/fonttools/commit/a696d5ba93270d5954f98e7cab5ddca8a02c1e32	Patch
https://github.com/fonttools/fonttools/security/advisories/GHSA-768j-98cg-p3fv	Exploit Vendor Advisory
https://github.com/fonttools/fonttools/security/advisories/GHSA-768j-98cg-p3fv	Exploit Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:fonttools:fonttools:*:*:*:*:*:python:*:*

History

18 Oct 2026, 18:10

Type	Values Removed	Values Added
Summary		(es) fontTools es una biblioteca para manipular fuentes, escrita en Python. En versiones desde la 4.33.0 hasta antes de la 4.60.2, el script fonttools varLib (o python3 -m fontTools.varLib) tiene una vulnerabilidad de escritura de archivo arbitraria que conduce a la ejecución remota de código cuando se procesa un archivo .designspace malicioso. La vulnerabilidad afecta la ruta de código main() de fontTools.varLib, utilizada por la CLI de fonttools varLib y cualquier código que invoque fontTools.varLib.main(). Este problema ha sido parcheado en la versión 4.60.2.

Information

Published : 2025-11-29 01:16

Updated : 2026-10-18 18:10

NVD link : CVE-2025-66034

Mitre link : CVE-2025-66034

CVE.ORG link : CVE-2025-66034

JSON object : View

Products Affected

fonttools

fonttools

CWE

CWE-91

XML Injection (aka Blind XPath Injection)

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