CVE-2022-26997
📋 TL;DR
CVE-2022-26997 is a critical command injection vulnerability in Arris TR3300 routers that allows attackers to execute arbitrary system commands via the upnp_ttl parameter. This affects Arris TR3300 router users running vulnerable firmware versions. Attackers can gain complete control of affected devices through network requests.
💻 Affected Systems
- Arris TR3300
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete device compromise allowing attackers to install persistent malware, pivot to internal networks, intercept all network traffic, and use the device as part of botnets.
Likely Case
Remote code execution leading to device takeover, credential theft, DNS hijacking, and participation in DDoS attacks.
If Mitigated
Limited impact if device is behind strict firewall rules, upnp is disabled, and network segmentation is implemented.
🎯 Exploit Status
Public proof-of-concept exists in GitHub repositories. Exploitation requires sending crafted HTTP requests to the router's upnp interface.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: v1.0.14 or later
Vendor Advisory: https://www.arris.com/support/security-advisories
Restart Required: Yes
Instructions:
1. Log into router admin interface. 2. Check for firmware updates. 3. Download and install latest firmware. 4. Reboot router after installation.
🔧 Temporary Workarounds
Disable UPnP
allTurn off Universal Plug and Play functionality to prevent exploitation via the vulnerable parameter.
Login to router admin -> Advanced -> UPnP -> Disable
Restrict Management Access
allLimit access to router management interface to trusted IP addresses only.
Login to router admin -> Firewall -> Access Control -> Add rules to restrict management interface access
🧯 If You Can't Patch
- Isolate affected routers in separate VLAN with strict firewall rules
- Implement network monitoring for suspicious upnp requests and command execution attempts
🔍 How to Verify
Check if Vulnerable:
Check router firmware version via admin interface. If version is v1.0.13 or earlier, device is vulnerable.Check Version:
Login to router admin interface and navigate to Status -> Device Info to view firmware versionVerify Fix Applied:
Verify firmware version is v1.0.14 or later after update. Test upnp functionality to ensure it still works without allowing command injection.📡 Detection & Monitoring
Log Indicators:
- Unusual upnp requests with shell metacharacters
- Multiple failed upnp requests from single source
- Router logs showing command execution attempts
Network Indicators:
- HTTP POST requests to upnp endpoints containing shell commands
- Unusual outbound connections from router to suspicious IPs
- DNS queries to known malicious domains from router
SIEM Query:
source="router_logs" AND (upnp_ttl CONTAINS "|" OR upnp_ttl CONTAINS ";" OR upnp_ttl CONTAINS "`" OR upnp_ttl CONTAINS "$")