CVE-2025-22905: Edimax RE11S Firmware RCE Vulnerability

CVE-2025-22905 Overview

CVE-2025-22905 is a command injection vulnerability affecting the Edimax RE11S wireless range extender running firmware version 1.11. The vulnerability exists in the /goform/mp endpoint, where the command parameter is improperly sanitized, allowing attackers to inject and execute arbitrary system commands on the device.

This flaw represents a severe security risk as it enables unauthenticated remote attackers to gain complete control over the affected device via the network interface. Successful exploitation could lead to full device compromise, network pivoting, data exfiltration, or the device being recruited into a botnet.

Critical Impact

Unauthenticated remote attackers can execute arbitrary commands on vulnerable Edimax RE11S devices, potentially compromising entire network segments.

Affected Products

• Edimax RE11S Firmware version 1.11
• Edimax RE11S Hardware Device

Discovery Timeline

• 2025-01-16 - CVE-2025-22905 published to NVD
• 2025-04-09 - Last updated in NVD database

Technical Details for CVE-2025-22905

Vulnerability Analysis

This command injection vulnerability (CWE-94: Improper Control of Generation of Code) occurs when user-supplied input to the command parameter at the /goform/mp endpoint is passed directly to a system shell without proper sanitization or validation. The web interface fails to adequately filter special characters and shell metacharacters, allowing attackers to break out of the intended command context and execute arbitrary commands with the privileges of the web server process.

On embedded devices like the RE11S range extender, the web server typically runs with elevated privileges, meaning successful exploitation often grants root-level access to the underlying Linux operating system. This allows attackers to modify firmware, install persistent backdoors, intercept network traffic, or use the compromised device as a pivot point for further attacks within the network.

Root Cause

The root cause of this vulnerability is insufficient input validation and sanitization in the firmware's web application. The command parameter value is concatenated directly into a system call or shell command without proper escaping or whitelisting of allowed commands. This violates secure coding practices that mandate treating all user input as untrusted and implementing strict input validation before processing.

Attack Vector

The attack vector is network-based and requires no authentication or user interaction. An attacker with network access to the device's web management interface can craft a malicious HTTP request to the /goform/mp endpoint with shell metacharacters injected into the command parameter.

The vulnerability can be exploited by appending shell command separators (such as ;, |, &&, or backticks) followed by arbitrary commands to the parameter value. For example, injecting ; id or $(whoami) would cause the injected command to execute on the target system. Technical details and proof-of-concept information are available in the GitHub Command Injection Exploit repository.

Detection Methods for CVE-2025-22905

Indicators of Compromise

• Unusual HTTP POST requests to /goform/mp containing shell metacharacters (;, |, &&, `, $()) in the command parameter
• Unexpected outbound network connections from the RE11S device to unknown external IP addresses
• Unauthorized processes or services running on the device
• Modified firmware files or configuration changes not initiated by administrators

Detection Strategies

• Deploy network intrusion detection signatures to identify HTTP requests to /goform/mp with suspicious payloads
• Monitor firewall logs for unusual traffic patterns originating from Edimax devices on the network
• Implement web application firewall rules to block requests containing command injection patterns targeting the affected endpoint
• Regularly audit device configurations and compare against known-good baselines

Monitoring Recommendations

• Enable logging on network devices to capture all traffic to and from Edimax range extenders
• Configure SIEM alerts for any access attempts to the /goform/mp endpoint from untrusted sources
• Establish baseline behavior for IoT devices and alert on deviations such as unexpected DNS queries or connection attempts

How to Mitigate CVE-2025-22905

Immediate Actions Required

• Restrict network access to the device's web management interface using firewall rules or network segmentation
• Place vulnerable devices on an isolated VLAN with no direct internet access
• Disable remote management features if not required for operations
• Monitor the Edimax website for firmware updates addressing this vulnerability

Patch Information

At the time of this writing, no official patch information has been published by Edimax. Organizations should monitor vendor communications and apply firmware updates as soon as they become available. Check the Edimax Security Information page for updates.

Workarounds

• Implement network-level access controls to restrict management interface access to trusted IP addresses only
• Deploy a web application firewall or reverse proxy with input validation rules in front of the device management interface
• Consider replacing vulnerable devices with alternative products if patches are not made available in a timely manner
• If the device must remain in use, ensure it is isolated from critical network segments and regularly monitored for signs of compromise

# Example: Firewall rule to restrict access to device management interface
# Replace 192.168.1.100 with the RE11S device IP and 10.0.0.0/24 with trusted admin subnet
iptables -A INPUT -d 192.168.1.100 -p tcp --dport 80 -s 10.0.0.0/24 -j ACCEPT
iptables -A INPUT -d 192.168.1.100 -p tcp --dport 80 -j DROP