CVE-2020-28622
📋 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 Nef polygon parsing to execute arbitrary code. 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 complete control over the affected system, potentially leading to data theft, ransomware deployment, or lateral movement.
Likely Case
Application crash leading to denial of service, with potential for limited code execution in the context of the vulnerable application.
If Mitigated
Application crash without code execution if memory protections (ASLR, DEP) are effective, but service disruption still occurs.
🎯 Exploit Status
Exploitation requires crafting malicious polygon files and convincing users/processes to parse them. No public exploit code is known.
🛠️ 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
allImplement strict validation of polygon files before processing with CGAL
Sandbox parsing
allRun CGAL polygon parsing in isolated containers or sandboxes
🧯 If You Can't Patch
- Disable Nef polygon parsing functionality if not required
- Implement network segmentation to isolate vulnerable systems
🔍 How to Verify
Check if Vulnerable:
Check CGAL version: dpkg -l | grep libcgal or check package manager for CGAL versionCheck Version:
cgal_create_cmake_script --version or check package managerVerify Fix Applied:
Verify CGAL version is 5.1.2 or later and applications have been recompiled📡 Detection & Monitoring
Log Indicators:
- Application crashes when processing polygon files
- Memory access violation errors in application logs
Network Indicators:
- Unexpected polygon file transfers to systems using CGAL
SIEM Query:
source="application.log" AND ("segmentation fault" OR "access violation") 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
