CVE-2023-44832
📋 TL;DR
This vulnerability in D-Link DIR-823G routers allows attackers to trigger a buffer overflow by sending specially crafted input to the MacAddress parameter in the SetWanSettings function. This can cause a Denial of Service (DoS) by crashing the device. Only users of the specific D-Link DIR-823G A1 hardware with firmware version V1.0.2B05 are affected.
💻 Affected Systems
- D-Link DIR-823G A1
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete device crash requiring physical reset, potentially leading to extended network downtime for affected users.
Likely Case
Temporary denial of service requiring device reboot, disrupting internet connectivity for connected devices.
If Mitigated
No impact if device is patched or workarounds are implemented.
🎯 Exploit Status
Exploit requires access to the device's management interface. The public PoC demonstrates the buffer overflow trigger.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Check D-Link security bulletin for latest patched version
Vendor Advisory: https://www.dlink.com/en/security-bulletin/
Restart Required: Yes
Instructions:
1. Visit D-Link support site. 2. Download latest firmware for DIR-823G A1. 3. Log into router admin interface. 4. Navigate to firmware update section. 5. Upload and apply new firmware. 6. Wait for reboot.
🔧 Temporary Workarounds
Restrict Management Access
allLimit access to router management interface to trusted IP addresses only
Disable Remote Management
allTurn off WAN-side management access if enabled
🧯 If You Can't Patch
- Replace affected device with updated model or different vendor product
- Isolate router on separate VLAN with strict access controls
🔍 How to Verify
Check if Vulnerable:
Check router web interface for firmware version. If it shows V1.0.2B05 on DIR-823G A1 hardware, it is vulnerable.Check Version:
Login to router admin interface and check System Status or Firmware Information pageVerify Fix Applied:
After firmware update, verify version no longer shows V1.0.2B05 and test SetWanSettings functionality.📡 Detection & Monitoring
Log Indicators:
- Multiple failed login attempts followed by SetWanSettings requests with malformed MacAddress parameters
- Router crash/reboot logs
Network Indicators:
- Unusual HTTP POST requests to router management interface with long MacAddress parameters
- Sudden loss of connectivity to router management interface
SIEM Query:
source="router_logs" AND ("SetWanSettings" OR "MacAddress") AND (length(field)>20 OR "buffer" OR "crash")