CVE-2021-1150
📋 TL;DR
This vulnerability allows authenticated remote attackers with administrator credentials to execute arbitrary commands with root privileges on affected Cisco Small Business routers. The vulnerability exists in the web-based management interface due to improper input validation. Attackers can exploit it by sending crafted HTTP requests to gain full control of the device.
💻 Affected Systems
- Cisco Small Business RV110W
- Cisco Small Business RV130
- Cisco Small Business RV130W
- Cisco Small Business RV215W
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete compromise of the router allowing attackers to intercept all network traffic, install persistent backdoors, pivot to internal networks, and use the device for further attacks.
Likely Case
Attackers with stolen or default admin credentials gain full control of the router to monitor traffic, redirect DNS, or use as a foothold for internal network attacks.
If Mitigated
With strong authentication and network segmentation, impact is limited to the router itself, though it could still be used as a pivot point.
🎯 Exploit Status
Exploitation requires valid admin credentials but is straightforward once credentials are obtained. No public exploit code is known.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: None available
Vendor Advisory: https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-rv-command-inject-LBdQ2KRN
Restart Required: No
Instructions:
No official patch is available. Cisco has not released software updates for these end-of-life products. Consider workarounds or replacement.
🔧 Temporary Workarounds
Disable Web Management Interface
allDisable the web-based management interface to prevent exploitation via HTTP requests
Access router CLI via SSH/Telnet
Navigate to web management settings
Disable HTTP/HTTPS management access
Restrict Management Access
allLimit management interface access to specific trusted IP addresses only
Configure firewall rules to allow management only from specific IPs
Disable remote management if not required
🧯 If You Can't Patch
- Replace affected routers with supported models that receive security updates
- Implement network segmentation to isolate routers from critical internal resources
🔍 How to Verify
Check if Vulnerable:
Check if device model is RV110W, RV130, RV130W, or RV215W and has web management enabledCheck Version:
Login to web interface and check System Information page, or use 'show version' in CLIVerify Fix Applied:
Verify web management interface is disabled or access is restricted to trusted IPs only📡 Detection & Monitoring
Log Indicators:
- Unusual HTTP POST requests to management interface
- Multiple failed login attempts followed by successful login
- Commands executed via web interface with unusual parameters
Network Indicators:
- HTTP requests with command injection patterns to router management ports
- Outbound connections from router to unusual external IPs
SIEM Query:
source="router_logs" AND (url="*cgi*" OR url="*cmd*" OR url="*exec*") AND (method="POST") AND (status="200")