CVE-2020-5146
📋 TL;DR
This vulnerability allows authenticated management users on SonicWall SMA100 appliances to execute arbitrary operating system commands via HTTP POST parameters. It affects SMA100 appliances running version 10.2.0.2-20sv and earlier. Attackers with management credentials can gain full system control.
💻 Affected Systems
- SonicWall SMA100 Appliance
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete compromise of the SMA100 appliance leading to network pivoting, data exfiltration, and deployment of persistent backdoors.
Likely Case
Privilege escalation from authenticated user to root/system-level access, enabling configuration changes, credential harvesting, and lateral movement.
If Mitigated
Limited impact if strong authentication controls, network segmentation, and least privilege principles are enforced.
🎯 Exploit Status
Exploitation requires authenticated access but is straightforward once credentials are obtained; no public proof-of-concept has been disclosed.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 10.2.0.2-21sv or later
Vendor Advisory: https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2020-0022
Restart Required: Yes
Instructions:
1. Log into the SMA100 management interface. 2. Navigate to System > Settings > Firmware. 3. Upload and install firmware version 10.2.0.2-21sv or later. 4. Reboot the appliance after installation.
🔧 Temporary Workarounds
Restrict Management Access
allLimit management interface access to trusted IP addresses using firewall rules.
Configure firewall to allow only specific source IPs to SMA100 management port (default 443)
Enforce Strong Authentication
allImplement multi-factor authentication and strong password policies for management users.
Enable MFA in SMA100 settings and enforce complex passwords
🧯 If You Can't Patch
- Isolate the SMA100 appliance in a dedicated network segment with strict access controls.
- Monitor and audit all management user activities and command execution attempts.
🔍 How to Verify
Check if Vulnerable:
Check the firmware version via the SMA100 web interface under System > Settings > Firmware.Check Version:
ssh admin@<sma100_ip> show version (if SSH enabled) or check web interfaceVerify Fix Applied:
Confirm the firmware version is 10.2.0.2-21sv or later in the same interface.📡 Detection & Monitoring
Log Indicators:
- Unusual POST requests to management endpoints, unexpected command execution in system logs, authentication from unusual IPs
Network Indicators:
- Suspicious outbound connections from SMA100 appliance, abnormal traffic patterns
SIEM Query:
source="sma100" AND (http_method="POST" AND uri="/cgi-bin/*" AND status=200) OR (event_type="command_injection")