CVE-2024-39962
📋 TL;DR
This vulnerability allows remote attackers to execute arbitrary code on D-Link DIR-823X AX3000 routers by sending a specially crafted HTTP request to the ntp_zone_val parameter. Attackers can gain full control of affected routers without authentication. All users of the specified router version are affected.
💻 Affected Systems
- D-Link DIR-823X AX3000 Dual-Band Gigabit Wireless Router
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete router compromise allowing attackers to intercept all network traffic, install persistent malware, pivot to internal networks, and use the router as part of a botnet.
Likely Case
Router takeover leading to DNS hijacking, credential theft from network traffic, and installation of cryptocurrency miners or other malware.
If Mitigated
Limited impact if router is behind firewall with restricted WAN access, though internal attackers could still exploit.
🎯 Exploit Status
Public proof-of-concept available showing simple HTTP POST exploitation. No authentication required.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: Unknown
Restart Required: Yes
Instructions:
1. Check D-Link support site for firmware updates
2. If update available, download and install via router web interface
3. Reboot router after installation
4. Verify firmware version has changed from v21_D240126
🔧 Temporary Workarounds
Disable Remote Management
allPrevent external access to router web interface
Restrict Web Interface Access
allLimit access to router admin interface to specific IPs
🧯 If You Can't Patch
- Replace affected router with different model or vendor
- Place router behind dedicated firewall with strict inbound rules
🔍 How to Verify
Check if Vulnerable:
Check router firmware version in web interface under System > Firmware. If version is v21_D240126, device is vulnerable.Check Version:
No CLI command; check via router web interface at System > FirmwareVerify Fix Applied:
Verify firmware version has changed from v21_D240126 after update.📡 Detection & Monitoring
Log Indicators:
- HTTP POST requests to /goform/set_ntp with unusual ntp_zone_val parameters
- Unusual process execution or system modifications
Network Indicators:
- HTTP traffic to router IP on port 80/443 with POST to /goform/set_ntp
- Unusual outbound connections from router
SIEM Query:
http.method:POST AND http.uri:"/goform/set_ntp" AND (http.user_agent:curl* OR http.user_agent:wget* OR http.user_agent:python*)