CVE-2019-1144
📋 TL;DR
A remote code execution vulnerability in Windows font library allows attackers to execute arbitrary code by tricking users into viewing malicious websites or opening crafted documents. This affects Windows systems with vulnerable font handling components. Users with administrative privileges face complete system compromise.
💻 Affected Systems
- Microsoft Windows
📦 What is this software?
Windows 10 by Microsoft
Windows 10 by Microsoft
Windows 10 by Microsoft
Windows 10 by Microsoft
Windows 10 by Microsoft
Windows 10 by Microsoft
Windows 10 by Microsoft
Windows 7 by Microsoft
Windows 8.1 by Microsoft
Windows Rt 8.1 by Microsoft
⚠️ Risk & Real-World Impact
Worst Case
Full system compromise allowing attacker to install programs, modify data, create accounts, and maintain persistence.
Likely Case
Targeted attacks via phishing emails with malicious documents leading to initial access and lateral movement.
If Mitigated
Limited impact if users have reduced privileges and security controls block suspicious documents/websites.
🎯 Exploit Status
Exploit requires user interaction but technical complexity is low once triggered. Public proof-of-concept exists.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: July 2019 security updates
Vendor Advisory: https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2019-1144
Restart Required: Yes
Instructions:
1. Apply Windows Update. 2. Install July 2019 security updates. 3. Restart system. 4. Verify update installation.
🔧 Temporary Workarounds
Disable font embedding in Office documents
windowsPrevents embedded fonts from being processed in Office applications
Use Microsoft Enhanced Mitigation Experience Toolkit (EMET)
windowsApply exploit mitigation controls
🧯 If You Can't Patch
- Restrict user privileges to limit impact if exploited
- Implement application whitelisting to prevent unauthorized program execution
🔍 How to Verify
Check if Vulnerable:
Check Windows Update history for July 2019 security updates or run 'systeminfo' commandCheck Version:
wmic qfe list | findstr KB4507453Verify Fix Applied:
Verify KB4507453 (Windows 10 v1903) or equivalent July 2019 security update is installed📡 Detection & Monitoring
Log Indicators:
- Unusual font library process crashes
- Suspicious document opens from external sources
Network Indicators:
- Downloads of font files from untrusted sources
- Malicious document delivery via email
SIEM Query:
EventID=1000 Source='Windows Error Reporting' AND ProcessName contains 'font'🔗 References
- http://packetstormsecurity.com/files/154085/Microsoft-Font-Subsetting-DLL-MergeFormat12Cmap-MakeFormat12MergedGlyphList-Double-Free.html
- https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2019-1144
- http://packetstormsecurity.com/files/154085/Microsoft-Font-Subsetting-DLL-MergeFormat12Cmap-MakeFormat12MergedGlyphList-Double-Free.html
- https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2019-1144
