CVE-2026-0581 Overview
A command injection vulnerability has been identified in the Tenda AC1206 router running firmware version 15.03.06.23. The vulnerability exists within the formBehaviorManager function located in the /goform/BehaviorManager endpoint of the httpd component. An attacker can exploit this vulnerability by manipulating the modulename, option, data, or switch arguments to inject and execute arbitrary system commands. This attack can be performed remotely over the network, making it particularly dangerous for exposed devices.
Critical Impact
Remote attackers with low privileges can inject arbitrary commands into the Tenda AC1206 router, potentially gaining control of the device, intercepting network traffic, or using it as a pivot point for further attacks on the internal network.
Affected Products
- Tenda AC1206 with firmware version 15.03.06.23
- Devices running the vulnerable httpd component with /goform/BehaviorManager endpoint
Discovery Timeline
- 2026-01-05 - CVE-2026-0581 published to NVD
- 2026-01-08 - Last updated in NVD database
Technical Details for CVE-2026-0581
Vulnerability Analysis
This vulnerability is classified as CWE-74 (Improper Neutralization of Special Elements in Output Used by a Downstream Component), commonly known as injection. The formBehaviorManager function in the Tenda AC1206 router's httpd service fails to properly sanitize user-supplied input before incorporating it into system commands.
When processing requests to the /goform/BehaviorManager endpoint, the function accepts several parameters including modulename, option, data, and switch. These parameters are passed to downstream system functions without adequate validation or sanitization, allowing an attacker to inject shell metacharacters and execute arbitrary commands with the privileges of the httpd process.
The exploit has been publicly disclosed and a proof-of-concept is available, increasing the likelihood of active exploitation. For detailed technical analysis, refer to the GitHub PoC Repository.
Root Cause
The root cause of this vulnerability lies in the lack of input validation and sanitization within the formBehaviorManager function. The function directly processes user-controlled parameters from HTTP requests without escaping or filtering shell metacharacters such as semicolons (;), pipes (|), backticks (`), or command substitution syntax ($()). This allows attackers to break out of the intended command context and inject their own system commands.
Attack Vector
The attack is network-based and requires low privileges to exploit. An attacker can send a crafted HTTP request to the /goform/BehaviorManager endpoint with malicious payloads embedded in the vulnerable parameters. The vulnerability manifests when user input containing command injection sequences is passed to underlying system functions. Successful exploitation could allow attackers to execute arbitrary commands, establish reverse shells, modify router configurations, or pivot to other devices on the network.
The attack does not require user interaction, making it suitable for automated exploitation. The publicly available proof-of-concept demonstrates the exploitation technique through crafted HTTP POST requests targeting the vulnerable form handler.
Detection Methods for CVE-2026-0581
Indicators of Compromise
- Unusual HTTP POST requests to /goform/BehaviorManager containing shell metacharacters in parameters
- Unexpected outbound network connections from the router to external IP addresses
- Modifications to router configuration files or unexpected new user accounts
- Unusual processes spawned by the httpd service on the router
Detection Strategies
- Deploy network intrusion detection rules to identify malicious payloads targeting /goform/BehaviorManager
- Monitor HTTP traffic for requests containing command injection patterns in modulename, option, data, or switch parameters
- Implement web application firewall (WAF) rules to block requests with shell metacharacters to Tenda device endpoints
- Review router logs for failed or suspicious authentication attempts and unusual administrative actions
Monitoring Recommendations
- Enable logging on the Tenda AC1206 device and forward logs to a central SIEM for analysis
- Monitor for unexpected configuration changes or firmware modifications
- Implement network segmentation to isolate IoT devices from critical network segments
- Periodically audit devices for unauthorized access or configuration changes
How to Mitigate CVE-2026-0581
Immediate Actions Required
- Restrict network access to the router's administrative interface from untrusted networks
- Implement firewall rules to block external access to the /goform/BehaviorManager endpoint
- Place the Tenda AC1206 router behind a properly configured firewall with egress filtering
- Consider disabling remote management features until a patch is available
- Monitor for vendor security advisories from Tenda
Patch Information
As of the last NVD update on 2026-01-08, no official patch has been released by Tenda for this vulnerability. Organizations should monitor the Tenda Official Website for firmware updates addressing this command injection vulnerability. Given the public availability of exploit code, applying any available patches should be treated as a high priority.
Additional information about this vulnerability can be found at VulDB #339473.
Workarounds
- Disable remote administration and only allow local management of the router
- Implement network access controls to restrict which hosts can communicate with the router's management interface
- Deploy a web application firewall or reverse proxy to filter malicious requests before they reach the device
- Consider replacing the vulnerable device with one from a vendor with active security support if no patch is forthcoming
# Example: Block external access to the vulnerable endpoint using iptables on a gateway
iptables -A FORWARD -p tcp --dport 80 -d <router_ip> -m string --string "/goform/BehaviorManager" --algo bm -j DROP
iptables -A FORWARD -p tcp --dport 443 -d <router_ip> -m string --string "/goform/BehaviorManager" --algo bm -j DROP
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
