CVE-2022-28915
📋 TL;DR
This CVE describes a command injection vulnerability in D-Link DIR-816 routers that allows attackers to execute arbitrary commands on the device. Attackers can exploit this by injecting malicious commands into the admuser and admpass parameters during administrative authentication. This affects users of D-Link DIR-816 A2 routers with vulnerable firmware versions.
💻 Affected Systems
- D-Link DIR-816 A2
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete device compromise allowing attackers to install persistent backdoors, intercept network traffic, pivot to internal networks, or brick the device.
Likely Case
Attackers gain administrative control of the router, enabling them to modify DNS settings, redirect traffic, or steal credentials from connected devices.
If Mitigated
Limited impact if device is behind firewall with restricted administrative access and network segmentation.
🎯 Exploit Status
Exploitation requires access to the administrative interface but does not require valid credentials. Proof-of-concept code is publicly available.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Check vendor for latest firmware
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-816 A2. 3. Log into router admin interface. 4. Navigate to System Tools > Firmware Upgrade. 5. Upload and apply new firmware. 6. Reboot router.
🔧 Temporary Workarounds
Disable Remote Administration
allPrevent external access to administrative interface
Log into router admin > Advanced > Remote Management > Disable
Restrict Administrative Access
allLimit administrative interface access to specific IP addresses
Log into router admin > Advanced > Firewall > Access Control
🧯 If You Can't Patch
- Isolate router on separate VLAN with strict firewall rules
- Implement network monitoring for unusual administrative access patterns
🔍 How to Verify
Check if Vulnerable:
Check firmware version in router admin interface under Status > Device InfoCheck Version:
curl -s http://router-ip/status.asp | grep FirmwareVerify Fix Applied:
Verify firmware version is updated beyond v1.10CNB04📡 Detection & Monitoring
Log Indicators:
- Unusual POST requests to /goform/setSysAdm with shell metacharacters
- Multiple failed login attempts followed by successful login
Network Indicators:
- Unusual outbound connections from router
- DNS changes not initiated by administrator
SIEM Query:
source="router.log" AND (uri="/goform/setSysAdm" AND (user="*;*" OR pass="*|*" OR user="*`*"))