CVE-2025-15276
📋 TL;DR
This vulnerability allows remote attackers to execute arbitrary code by tricking users into opening malicious SFD font files in FontForge. Attackers can achieve remote code execution in the context of the current user process. Users and organizations using FontForge for font editing are affected.
💻 Affected Systems
- FontForge
📦 What is this software?
Fontforge by Fontforge
⚠️ Risk & Real-World Impact
Worst Case
Full system compromise via remote code execution with user privileges, potentially leading to data theft, ransomware deployment, or lateral movement.
Likely Case
Local privilege escalation or malware installation when users open malicious font files from untrusted sources.
If Mitigated
Limited impact with proper file validation and user awareness preventing exploitation.
🎯 Exploit Status
Requires user interaction to open malicious file. Exploit details are available to ZDI researchers but not publicly disclosed.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Check FontForge GitHub releases or vendor advisory for specific version
Vendor Advisory: https://github.com/fontforge/fontforge/security/advisories (check for CVE-2025-15276)
Restart Required: Yes
Instructions:
1. Check current FontForge version
2. Visit FontForge GitHub releases page
3. Download and install the latest patched version
4. Restart FontForge and any related services
🔧 Temporary Workarounds
Disable SFD file association
allPrevent FontForge from automatically opening SFD files by changing file associations
Windows: Use 'Default Apps' settings to change .sfd association
Linux: Update mime types or use 'xdg-mime' to change handler
macOS: Use 'Get Info' on .sfd files to change 'Open With'
User awareness training
allTrain users to avoid opening SFD files from untrusted sources
🧯 If You Can't Patch
- Implement application whitelisting to block FontForge execution
- Use network segmentation to isolate FontForge systems from critical assets
🔍 How to Verify
Check if Vulnerable:
Check FontForge version against patched release from vendor advisoryCheck Version:
fontforge --version (Linux/macOS) or check About dialog (Windows)Verify Fix Applied:
Verify installed version matches or exceeds patched version from advisory📡 Detection & Monitoring
Log Indicators:
- Unusual FontForge process spawning child processes
- FontForge crashes or abnormal termination when processing files
Network Indicators:
- Downloads of SFD files from untrusted sources
- Outbound connections from FontForge process to suspicious IPs
SIEM Query:
process_name:"fontforge" AND (child_process_spawn OR process_crash)