VULNERABILITY INTELLIGENCE
CVE-2025-66034
CVSS score9.8 CRITICAL
EPSS probability0.59%
CISA KEVNot currently listed
Published2025-11-29
Last modified2026-10-18
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.