CVE-2020-20665
📋 TL;DR
CVE-2020-20665 is a memory leak vulnerability in rudp v0.6's main.c component that allows attackers to cause denial of service through resource exhaustion. This affects systems using the vulnerable rudp library for reliable UDP communication. The vulnerability is particularly concerning for applications that handle high volumes of network traffic.
💻 Affected Systems
- rudp
📦 What is this software?
Rudp by Rudp Project
⚠️ Risk & Real-World Impact
Worst Case
Complete system crash or service disruption due to memory exhaustion, potentially leading to extended downtime and requiring manual intervention to restart affected services.
Likely Case
Gradual performance degradation and eventual service unavailability as memory consumption increases over time, particularly under sustained network load.
If Mitigated
Minimal impact with proper monitoring and restart mechanisms in place, though some performance degradation may still occur during peak usage.
🎯 Exploit Status
Exploitation requires sending network traffic to trigger the memory leak, but no public exploit code has been documented.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: v0.7 or later
Vendor Advisory: https://github.com/cloudwu/rudp/issues/6
Restart Required: Yes
Instructions:
1. Check current rudp version. 2. Update to rudp v0.7 or later. 3. Recompile any applications using rudp. 4. Restart affected services.
🔧 Temporary Workarounds
Service Restart Schedule
linuxImplement regular service restarts to clear accumulated memory before exhaustion occurs
systemctl restart [service_name]
Memory Limit Enforcement
linuxUse cgroups or container limits to prevent complete system memory exhaustion
systemd-run --unit=rudp-service --slice=memory-low.slice --property=MemoryLimit=512M [command]
🧯 If You Can't Patch
- Implement aggressive memory monitoring with automated alerts when usage exceeds thresholds
- Deploy behind load balancers with health checks to fail over to healthy instances
🔍 How to Verify
Check if Vulnerable:
Check if rudp v0.6 is installed: find / -name "*rudp*" -type f 2>/dev/null | xargs grep -l "0.6"Check Version:
strings /path/to/binary | grep -i rudpVerify Fix Applied:
Verify rudp version is v0.7 or later: grep -r "rudp.*version" /path/to/application/📡 Detection & Monitoring
Log Indicators:
- Unusual memory growth patterns in application logs
- Frequent out-of-memory errors or crashes
Network Indicators:
- Increased UDP traffic to affected services
- Unusual packet patterns triggering the rudp implementation
SIEM Query:
source="*rudp*" AND ("memory" OR "crash" OR "restart")