CVE-2026-20080
📋 TL;DR
This vulnerability in Cisco IEC6400 Wireless Backhaul Edge Compute Software allows unauthenticated remote attackers to cause a denial of service (DoS) by flooding the SSH service, making it unresponsive. Only the SSH service is affected while other system operations remain stable. Organizations using vulnerable versions of this Cisco software are at risk.
💻 Affected Systems
- Cisco IEC6400 Wireless Backhaul Edge Compute Software
⚠️ Manual Verification Required
This CVE does not have specific version information in our database, so automatic vulnerability detection cannot determine if your system is affected.
Why? The CVE database entry doesn't specify which versions are vulnerable (no version ranges provided by the vendor/NVD).
🔒 Custom verification scripts are available for registered users. Sign up free to download automated test scripts.
- Review the CVE details at NVD
- Check vendor security advisories for your specific version
- Test if the vulnerability is exploitable in your environment
- Consider updating to the latest version as a precaution
⚠️ Risk & Real-World Impact
Worst Case
SSH service becomes completely unavailable during attack, preventing remote administration and potentially disrupting management operations.
Likely Case
Temporary SSH service disruption during attack periods, requiring manual intervention or waiting for attack to stop.
If Mitigated
Minimal impact with proper network controls and monitoring in place.
🎯 Exploit Status
Simple DoS attack requiring only network access to SSH port.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Check Cisco advisory for specific fixed version
Vendor Advisory: https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-iec6400-Pem5uQ7v
Restart Required: Yes
Instructions:
1. Review Cisco advisory 2. Download and apply recommended software update 3. Restart affected devices 4. Verify SSH service functionality
🔧 Temporary Workarounds
Network Access Control
allRestrict SSH access to trusted IP addresses only
Configure firewall rules to limit SSH access to management networks
SSH Rate Limiting
linuxImplement connection rate limiting on SSH service
Configure SSH daemon with MaxStartups and MaxAuthTries restrictions
🧯 If You Can't Patch
- Implement network segmentation to restrict SSH access
- Deploy intrusion prevention systems (IPS) with DoS protection
🔍 How to Verify
Check if Vulnerable:
Check software version against Cisco advisory and test SSH service resilience to connection floodsCheck Version:
Check device software version via CLI or web interfaceVerify Fix Applied:
Verify software version is updated and test SSH service under simulated load📡 Detection & Monitoring
Log Indicators:
- High volume of failed SSH connection attempts
- SSH service restart messages
- Connection timeout errors
Network Indicators:
- Unusual high volume of traffic to SSH port (22)
- Multiple rapid connection attempts from single source
SIEM Query:
source_port=22 AND (event_count > threshold) OR (connection_attempts > normal_baseline)