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TI-2025-40560 Aliases CVE-2025-66034GHSA-768j-98cg-p3fv

fontTools is Vulnerable to Arbitrary File Write and XML injection in fontTools.varLib

Priority HIGH 75CWE-91Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
High · High · High
Fix status
Partial Red Hat: 2 fixed, 3 without a fix

Attack profile from CVSS 3.1 · NVD. Fix status from CNA, GitHub and Red Hat.

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.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00587 48th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Partial fonttools (fonttools): 4.60.2fonttools (PyPI): 4.60.2Red Hat: 3 advisoriesRed Hat: 2 fixed, 3 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
fonttoolsfonttools4.33.0 to before 4.60.24.60.2Patch availableCNA
—fonttools (PyPI)4.33.0 to before 4.60.24.60.2Patch availableGHSA-768j-98cg-p3fv
  • fonttools Vendorfonttools Affected 4.33.0 to before 4.60.2 Fixed in 4.60.2 Patch available CNA
  • fonttools (PyPI) Vendor— Affected 4.33.0 to before 4.60.2 Fixed in 4.60.2 Patch available GHSA-768j-98cg-p3fv

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:fonttools:fonttools:*:*:*:*:*:python:*:*4.33.0 to before 4.60.2Vulnerablefonttools
  • cpe:2.3:a:fonttools:fonttools:*:*:*:*:*:python:*:* Versions 4.33.0 to before 4.60.2 Vulnerable ·fonttools

Remediation

  • Fix · CNA fonttools (fonttools) Fixed in 4.60.2
  • Fix · GHSA-768j-98cg-p3fv fonttools (PyPI) Fixed in 4.60.2 Advisory →

Red Hat 3 advisories

  • RHSA-2026:3713 Released 2026-03-04 · Red Hat rating Critical
    RHOAI 3.3 - Red Hat OpenShift AI
    • Red Hat OpenShift AI 3.3 registry.redhat.io/rhoai/odh-built-in-detector-rhel9, registry.redhat.io/rhoai/odh-dashboard-rhel9, registry.redhat.io/rhoai/odh-data-science-pipelines-argo-argoexec-rhel9 +47
  • RHSA-2026:2695 Released 2026-02-12 · Red Hat rating Important
    RHOAI 2.25.2 - Red Hat OpenShift AI
    • Red Hat OpenShift AI 2.25 registry.redhat.io/rhoai/odh-dashboard-rhel9, registry.redhat.io/rhoai/odh-data-science-pipelines-argo-argoexec-rhel9, registry.redhat.io/rhoai/odh-data-science-pipelines-argo-workflowcontroller-rhel9 +13
  • RHSA-2026:2106 Released 2026-02-05 · Red Hat rating Important
    RHOAI 2.25.2 - Red Hat OpenShift AI
    • Red Hat OpenShift AI 2.25 registry.redhat.io/rhoai/odh-caikit-nlp-rhel9, registry.redhat.io/rhoai/odh-caikit-tgis-serving-rhel9, registry.redhat.io/rhoai/odh-dashboard-rhel9 +47

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Ansible Automation Platform 2AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux 7AffectedNo fix planned: Out of support scope
Red Hat Enterprise Linux AI (RHEL AI)AffectedNo fix planned: Out of support scope
Red Hat OpenShift AI 2.25Fixed RHSA-2026:2106, RHSA-2026:2695
Red Hat OpenShift AI 3.3Fixed RHSA-2026:3713
Not affected: 2 products
  • Red Hat OpenShift AI 2.25
  • Red Hat OpenShift AI 3.3

Timeline

  1. 2026-10-02 Threatist record created from CVE-2025-66034
  2. 2026-10-03 Alias added: GHSA-768j-98cg-p3fv

References

Exploit 1

Patch 1

Advisory 1

Other 1

  • TI-2023-24160 fonttools XML External Entity Injection (XXE) Vulnerability CVSS 3.1HIGH 7.5

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences