CVE-2026-2142
📋 TL;DR
This CVE describes a remote OS command injection vulnerability in D-Link DIR-823X routers. Attackers can execute arbitrary commands on affected devices by manipulating the QoS configuration function. All users of vulnerable DIR-823X routers are affected.
💻 Affected Systems
- D-Link DIR-823X
⚠️ 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
Complete device compromise allowing attackers to install persistent backdoors, pivot to internal networks, or use the device for botnet activities.
Likely Case
Attackers gain shell access to execute commands, potentially stealing credentials, modifying configurations, or disrupting network services.
If Mitigated
With proper network segmentation and firewall rules, impact is limited to the router itself without lateral movement.
🎯 Exploit Status
Public exploit code is available on GitHub. Attack requires network access to the router's web interface (typically port 80/443).
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: https://www.dlink.com/
Restart Required: Yes
Instructions:
1. Check D-Link website for firmware updates. 2. Download latest firmware for DIR-823X. 3. Log into router web interface. 4. Navigate to firmware update section. 5. Upload and apply new firmware. 6. Reboot router.
🔧 Temporary Workarounds
Disable Remote Management
allPrevent external access to the vulnerable web interface
Log into router admin panel -> Advanced -> Remote Management -> Disable
Network Segmentation
linuxIsolate router management interface from untrusted networks
iptables -A INPUT -p tcp --dport 80 -s ! 192.168.1.0/24 -j DROP
iptables -A INPUT -p tcp --dport 443 -s ! 192.168.1.0/24 -j DROP
🧯 If You Can't Patch
- Replace vulnerable device with supported model
- Implement strict firewall rules to block all external access to router management interface
🔍 How to Verify
Check if Vulnerable:
Check firmware version in router web interface under System -> Firmware. If version is 250416, device is vulnerable.Check Version:
curl -s http://router-ip/goform/getSysInfo | grep firmwareVerify Fix Applied:
After firmware update, verify version has changed from 250416. Test QoS configuration function for command injection.📡 Detection & Monitoring
Log Indicators:
- Unusual POST requests to /goform/set_qos with shell metacharacters
- Multiple failed login attempts followed by QoS configuration changes
Network Indicators:
- Unusual outbound connections from router to unknown IPs
- Traffic patterns suggesting command-and-control communication
SIEM Query:
source="router-logs" AND (uri="/goform/set_qos" AND (method="POST") AND (body CONTAINS "|" OR body CONTAINS ";" OR body CONTAINS "`"))