CVE-2026-2143
📋 TL;DR
This CVE describes a remote command injection vulnerability in D-Link DIR-823X routers. Attackers can execute arbitrary operating system commands by manipulating DDNS service parameters. All users of affected D-Link DIR-823X routers with vulnerable firmware are at risk.
💻 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, intercept traffic, or brick the device.
Likely Case
Attackers gain shell access to execute commands, potentially stealing credentials, modifying configurations, or launching attacks against internal systems.
If Mitigated
If properly segmented and monitored, impact limited to the router itself with no lateral movement to other systems.
🎯 Exploit Status
Public exploit code is available. The vulnerability requires no authentication and has simple exploitation vectors.
🛠️ 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 admin interface. 4. Navigate to firmware update section. 5. Upload and apply new firmware. 6. Reboot router.
🔧 Temporary Workarounds
Disable DDNS Service
allTurn off the vulnerable DDNS service to prevent exploitation
Login to router admin interface and disable DDNS service in network settings
Restrict Management Access
allLimit router management interface access to trusted IPs only
Configure firewall rules to restrict access to router admin interface (typically port 80/443)
🧯 If You Can't Patch
- Segment router on isolated network segment to limit lateral movement
- Implement strict network monitoring for unusual outbound connections from router
🔍 How to Verify
Check if Vulnerable:
Check router firmware version in admin interface. If version is 250416, device is vulnerable.Check Version:
Check router web interface at System > Firmware or via SSH if enabled: cat /proc/versionVerify Fix Applied:
After firmware update, verify version number has changed from 250416 and test DDNS functionality.📡 Detection & Monitoring
Log Indicators:
- Unusual POST requests to /goform/set_ddns with shell metacharacters
- Unexpected processes spawned from router services
- Failed authentication attempts to router admin interface
Network Indicators:
- Unusual outbound connections from router IP
- Traffic to known malicious IPs from router
- Port scanning originating from router
SIEM Query:
source="router_logs" AND (uri="/goform/set_ddns" AND (payload CONTAINS "|" OR payload CONTAINS ";" OR payload CONTAINS "`"))