CVE-2025-66034 (GCVE-0-2025-66034)

Vulnerability from cvelistv5 – Published: 2025-11-29 01:07 – Updated: 2025-12-01 14:11
VLAI
Title
fontTools is Vulnerable to Arbitrary File Write and XML injection in fontTools.varLib
Summary
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.
Severity
6.3 (Medium)
CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:C/C:N/I:H/A:L
SSVC
Exploitation: poc Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2025-12-01 13:56 UTC
CWE
  • CWE-91 - XML Injection (aka Blind XPath Injection)
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 8035 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
fonttools fonttools Affected: >= 4.33.0, < 4.60.2
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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