CVE-2022-27001
📋 TL;DR
CVE-2022-27001 is a critical command injection vulnerability in Arris TR3300 routers that allows attackers to execute arbitrary system commands via the DHCP hostname parameter. This affects Arris TR3300 router users running vulnerable firmware versions. Attackers can gain complete control of affected devices.
💻 Affected Systems
- Arris TR3300
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Full router compromise allowing attackers to intercept all network traffic, install persistent backdoors, pivot to internal networks, and use the router for botnet activities.
Likely Case
Router takeover enabling traffic interception, DNS hijacking, credential theft, and lateral movement to connected devices.
If Mitigated
Limited impact if isolated in lab environment with no internet access and strict network segmentation.
🎯 Exploit Status
Public GitHub repository contains proof-of-concept. Exploitation requires sending crafted DHCP requests but no authentication needed.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: v1.0.14 or later (check vendor for latest)
Vendor Advisory: https://www.arris.com/support/security-advisories
Restart Required: Yes
Instructions:
1. Log into router admin interface. 2. Navigate to firmware update section. 3. Download latest firmware from Arris support site. 4. Upload and apply update. 5. Reboot router.
🔧 Temporary Workarounds
Disable DHCP server
allDisable the router's DHCP server function to prevent exploitation via hostname parameter
Login to router admin > Network Settings > DHCP Server > Disable
Network segmentation
allIsolate router management interface from untrusted networks
Configure firewall rules to restrict access to router admin interface
🧯 If You Can't Patch
- Replace affected routers with patched or different models
- Implement strict network monitoring for unusual DHCP traffic patterns
🔍 How to Verify
Check if Vulnerable:
Check firmware version in router admin interface. If version is v1.0.13 or earlier, device is vulnerable.Check Version:
Login to router web interface and check System Information or Firmware Status pageVerify Fix Applied:
Verify firmware version shows v1.0.14 or later after update. Test DHCP functionality remains operational.📡 Detection & Monitoring
Log Indicators:
- Unusual DHCP requests with long or special characters in hostname field
- Router system logs showing command execution attempts
Network Indicators:
- DHCP requests containing shell metacharacters or command sequences
- Unexpected outbound connections from router
SIEM Query:
dhcp.hostname contains "|" OR dhcp.hostname contains ";" OR dhcp.hostname contains "$"