CVE-2022-29558
📋 TL;DR
CVE-2022-29558 is a command injection vulnerability in Realtek's rtl819x-SDK web interface that allows attackers to execute arbitrary commands on affected devices. This affects routers and access points using Realtek's SDK before version 3.6.1. Attackers can potentially gain full control of vulnerable devices.
💻 Affected Systems
- Realtek rtl819x-SDK based routers and access points
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete device compromise allowing persistent backdoor installation, network pivoting, credential theft, and participation in botnets.
Likely Case
Remote code execution leading to device takeover, network traffic interception, and lateral movement within the network.
If Mitigated
Limited impact if web interface is disabled or network segmentation prevents access to vulnerable interfaces.
🎯 Exploit Status
Exploitation requires access to the web interface but authentication status may vary by device implementation.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: v3.6.1 or later
Vendor Advisory: https://www.realtek.com/images/safe-report/Realtek_APRouter_SDK_Advisory-CVE-2022-29558.pdf
Restart Required: Yes
Instructions:
1. Contact device manufacturer for firmware updates. 2. Apply firmware update to affected devices. 3. Reboot devices after update. 4. Verify version is 3.6.1 or higher.
🔧 Temporary Workarounds
Disable Web Management Interface
allDisable the vulnerable web interface if not required for operations
Device-specific - consult manufacturer documentation
Network Segmentation
linuxRestrict access to management interfaces using firewall rules
iptables -A INPUT -p tcp --dport 80 -j DROP
iptables -A INPUT -p tcp --dport 443 -j DROP
🧯 If You Can't Patch
- Implement strict network access controls to limit who can reach the web interface
- Monitor for suspicious web interface activity and command execution attempts
🔍 How to Verify
Check if Vulnerable:
Check device firmware version against Realtek SDK version. If using SDK version <3.6.1, device is vulnerable.Check Version:
Device-specific - typically available in web interface or via SSH: cat /proc/version or similarVerify Fix Applied:
Verify firmware version shows SDK 3.6.1 or higher after update📡 Detection & Monitoring
Log Indicators:
- Unusual command execution in web interface logs
- Suspicious POST requests to web management endpoints
- Unexpected system command execution
Network Indicators:
- Unusual outbound connections from routers
- Traffic to known malicious IPs from router
- Unexpected port scans originating from router
SIEM Query:
source="router_logs" AND ("cmd=" OR "exec=" OR "system(") AND status=200