CVE-2020-28614
📋 TL;DR
This vulnerability in CGAL library allows remote code execution through specially crafted polygon files. An attacker can exploit out-of-bounds read and type confusion vulnerabilities in Nef polygon parsing to potentially execute arbitrary code. Systems using CGAL for computational geometry operations with untrusted input are affected.
💻 Affected Systems
- CGAL (Computational Geometry Algorithms Library)
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Remote attacker gains full system control through arbitrary code execution, potentially leading to complete system compromise, data theft, or ransomware deployment.
Likely Case
Application crash leading to denial of service, with potential for limited code execution depending on memory layout and exploit sophistication.
If Mitigated
Application crashes safely without code execution due to modern exploit mitigations like ASLR and DEP.
🎯 Exploit Status
Exploitation requires crafting malicious polygon files and convincing users/processes to parse them. Type confusion vulnerabilities can be complex to exploit reliably.
🛠️ 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. 4. For Linux distributions, use package manager: 'sudo apt update && sudo apt upgrade libcgal-dev' (Debian/Ubuntu) or 'sudo yum update cgal' (RHEL/CentOS).
🔧 Temporary Workarounds
Input Validation
allImplement strict input validation for polygon files before passing to CGAL parser
Disable Nef Polygon Parsing
allIf not required, disable or remove Nef polygon parsing functionality from application
🧯 If You Can't Patch
- Implement strict file type validation and reject untrusted polygon files
- Run CGAL applications in sandboxed/containerized environments with minimal privileges
🔍 How to Verify
Check if Vulnerable:
Check CGAL version: 'pkg-config --modversion cgal' or check installed package version in package managerCheck Version:
pkg-config --modversion cgal || dpkg -l | grep libcgal || rpm -qa | grep cgalVerify Fix Applied:
Verify CGAL version is 5.1.2 or later and recompile applications with updated library📡 Detection & Monitoring
Log Indicators:
- Application crashes with segmentation faults
- Unexpected memory access errors in CGAL-related processes
- Abnormal termination of geometry processing applications
Network Indicators:
- Unusual file uploads to geometry processing services
- Multiple failed parsing attempts of polygon files
SIEM Query:
source="application.log" AND ("segmentation fault" OR "SIGSEGV") AND process="*cgal*"🔗 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
