CVE-2025-66034
6.3 · MEDIUMOverview
CVE-2025-66034 is a medium-severity vulnerability affecting fonttools fonttools. It was published on November 29, 2025 and has a CVSS 3.1 base score of 6.3 (MEDIUM).
This vulnerability has a CVSS 3.1 base score of 6.3, rated MEDIUM. It requires local or adjacent network access to exploit. No authentication or special privileges are required for exploitation.
Technical 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.
Remediation
Check the references section for vendor advisories and patches from fonttools. Update fonttools to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
Affected Products
| Vendor | Product | Versions | Status |
|---|---|---|---|
| fonttools | fonttools | >= 4.33.0, < 4.60.2 | Affected |
Frequently Asked Questions
What is CVE-2025-66034?
CVE-2025-66034 is a medium-severity vulnerability affecting fonttools fonttools. It was published on November 29, 2025 and has a CVSS 3.1 base score of 6.3 (MEDIUM).
How severe is CVE-2025-66034?
This vulnerability has a CVSS 3.1 base score of 6.3, rated MEDIUM. It requires local or adjacent network access to exploit. No authentication or special privileges are required for exploitation.
How do I fix or remediate CVE-2025-66034?
Check the references section for vendor advisories and patches from fonttools. Update fonttools to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2025-66034?
CyberStrike's AI-powered security agents can automatically detect CVE-2025-66034 across your infrastructure using autonomous pentesting, DAST scanning, and HackBrowser. The platform continuously monitors for known vulnerabilities and provides actionable remediation guidance prioritized by real-world exploitability.
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