CVE-2020-28632
📋 TL;DR
This vulnerability in CGAL library allows remote code execution through specially crafted polygon files. Attackers can exploit out-of-bounds read and type confusion vulnerabilities in the Nef polygon-parsing functionality. Systems using CGAL for computational geometry operations are affected.
💻 Affected Systems
- CGAL (Computational Geometry Algorithms Library)
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Full system compromise with attacker gaining arbitrary code execution privileges on the affected system.
Likely Case
Application crash leading to denial of service, with potential for remote code execution in specific configurations.
If Mitigated
Application crash without code execution if memory protections are enabled.
🎯 Exploit Status
Exploitation requires specially crafted polygon files and knowledge of the vulnerable parsing functionality.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: CGAL-5.1.2 and later
Vendor Advisory: https://www.cgal.org/
Restart Required: Yes
Instructions:
1. Update CGAL to version 5.1.2 or later. 2. Recompile applications using CGAL. 3. Restart affected services.
🔧 Temporary Workarounds
Input validation
allValidate polygon files before processing with CGAL
Disable Nef polygon parsing
allDisable or restrict use of Nef polygon functionality if not required
🧯 If You Can't Patch
- Implement strict input validation for polygon files
- Run CGAL applications with reduced privileges and memory protection mechanisms
🔍 How to Verify
Check if Vulnerable:
Check CGAL version with: cgal_version or examine package manager outputCheck Version:
cgal_version || dpkg -l | grep libcgal || rpm -qa | grep -i cgalVerify Fix Applied:
Verify CGAL version is 5.1.2 or later📡 Detection & Monitoring
Log Indicators:
- Application crashes when processing polygon files
- Memory access violation errors
Network Indicators:
- Unexpected file uploads to CGAL applications
SIEM Query:
Application:CGAL AND (EventID:1000 OR SegmentationFault)🔗 References
- https://lists.debian.org/debian-lts-announce/2022/12/msg00011.html
- https://security.gentoo.org/glsa/202305-34
- https://talosintelligence.com/vulnerability_reports/TALOS-2020-1225
- https://lists.debian.org/debian-lts-announce/2022/12/msg00011.html
- https://security.gentoo.org/glsa/202305-34
- https://talosintelligence.com/vulnerability_reports/TALOS-2020-1225
