CVE-2020-23026
📋 TL;DR
This CVE describes a NULL pointer dereference vulnerability in dhrystone 2.1's dhry_1.c file that causes the program to crash, resulting in denial of service. The vulnerability affects systems running dhrystone 2.1, which is a benchmark tool used for CPU performance testing. While primarily a testing tool, any system using dhrystone could experience service disruption.
💻 Affected Systems
- dhrystone
📦 What is this software?
Dhrystone by Dhrystone Project
⚠️ Risk & Real-World Impact
Worst Case
Complete system crash or service disruption of any application that incorporates dhrystone functionality, potentially affecting system stability.
Likely Case
Application crash when dhrystone benchmark is executed with specific conditions triggering the NULL pointer dereference.
If Mitigated
Minimal impact if dhrystone is not actively used in production environments or if proper input validation prevents triggering the vulnerability.
🎯 Exploit Status
The vulnerability is in the main() function and can be triggered by running the program with specific conditions. Since dhrystone is open source, exploit code could be easily developed.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Not available
Vendor Advisory: No official vendor advisory found
Restart Required: No
Instructions:
1. Remove dhrystone 2.1 from affected systems
2. Upgrade to a newer version if available
3. Consider using alternative benchmarking tools
🔧 Temporary Workarounds
Remove dhrystone 2.1
allUninstall or remove the vulnerable dhrystone 2.1 package from the system
rm -f /path/to/dhrystone-2.1
Restrict execution permissions
linuxChange file permissions to prevent execution of the vulnerable binary
chmod -x /path/to/dhrystone-2.1
🧯 If You Can't Patch
- Isolate systems running dhrystone from production environments
- Implement strict access controls to prevent unauthorized execution of dhrystone
🔍 How to Verify
Check if Vulnerable:
Check if dhrystone 2.1 exists on the system: find / -name '*dhrystone*' -type f 2>/dev/nullCheck Version:
If dhrystone is found, run: ./dhrystone --version 2>&1 | grep -i versionVerify Fix Applied:
Verify dhrystone 2.1 has been removed or permissions have been restricted📡 Detection & Monitoring
Log Indicators:
- Segmentation fault errors in system logs
- Core dumps from dhrystone process
Network Indicators:
- No network indicators - this is a local vulnerability
SIEM Query:
Process execution logs showing dhrystone followed by crash/segfault events