CVE-2025-6328
📋 TL;DR
A critical stack-based buffer overflow vulnerability in D-Link DIR-815 router firmware allows remote attackers to execute arbitrary code. This affects the hedwig.cgi component, enabling potential full system compromise. All users of D-Link DIR-815 RevA version 1.01 are vulnerable.
💻 Affected Systems
- D-Link DIR-815 RevA
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution leading to complete router takeover, credential theft, network traffic interception, and lateral movement into connected networks.
Likely Case
Router compromise leading to botnet recruitment, DNS hijacking, or credential harvesting from connected devices.
If Mitigated
Limited impact if isolated from internet and internal networks, though still vulnerable to local network attacks.
🎯 Exploit Status
Public exploit code exists on GitHub. The vulnerability requires no authentication and has straightforward exploitation.
🛠️ 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. If update available, download from official site. 3. Log into router admin 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 router administration interface
Network Segmentation
allIsolate router management interface to separate VLAN
🧯 If You Can't Patch
- Replace affected hardware with supported, patched equipment
- Implement strict network access controls to limit exposure to router management interface
🔍 How to Verify
Check if Vulnerable:
Check router firmware version in admin interface. If version is 1.01 on DIR-815 RevA, device is vulnerable.Check Version:
Check router web interface or use: curl -s http://router-ip/ | grep -i versionVerify Fix Applied:
Verify firmware version has been updated to a version later than 1.01. Check that hedwig.cgi no longer accepts malformed requests.📡 Detection & Monitoring
Log Indicators:
- Unusual POST requests to hedwig.cgi
- Large buffer overflow patterns in web logs
- Multiple failed exploit attempts
Network Indicators:
- Unusual traffic patterns to router management port
- Exploit kit signatures targeting hedwig.cgi
SIEM Query:
source="router_logs" AND (uri="*hedwig.cgi*" AND (data_size>1000 OR pattern="*overflow*"))