CVE-2026-5962: Tenda CH22 Path Traversal Vulnerability

CVE-2026-5962 Overview

A path traversal vulnerability has been identified in the Tenda CH22 router firmware version 1.0.0.6(468). This security flaw exists within the R7WebsSecurityHandlerfunction function of the httpd component, allowing attackers to manipulate file paths to access directories and files outside of the intended directory structure. The vulnerability can be exploited remotely over the network, and public exploit information is now available.

Critical Impact

Remote attackers can exploit this path traversal vulnerability to read sensitive configuration files, access system credentials, or potentially access other protected resources on the affected Tenda CH22 device without authentication.

Affected Products

• Tenda CH22 firmware version 1.0.0.6(468)
• Tenda CH22 httpd web server component
• R7WebsSecurityHandlerfunction function within the httpd service

Discovery Timeline

• 2026-04-09 - CVE-2026-5962 published to NVD
• 2026-04-09 - Last updated in NVD database

Technical Details for CVE-2026-5962

Vulnerability Analysis

This path traversal vulnerability (CWE-22) affects the R7WebsSecurityHandlerfunction function within the httpd component of Tenda CH22 routers. The vulnerability occurs when the function fails to properly sanitize user-supplied input before using it in file path operations. When processing HTTP requests, the web server does not adequately validate directory traversal sequences (such as ../), allowing an attacker to escape the intended web root directory and access arbitrary files on the device's filesystem.

The network-accessible nature of this vulnerability means that any attacker who can reach the device's web interface can attempt exploitation. The public availability of exploit information increases the risk profile, as threat actors can readily leverage this knowledge to target vulnerable devices.

Root Cause

The root cause of this vulnerability lies in improper input validation within the R7WebsSecurityHandlerfunction. The function fails to sanitize path traversal sequences from user-supplied input before constructing file paths. This missing validation allows attackers to inject directory traversal characters that navigate outside the expected directory boundaries, enabling access to sensitive files on the device's filesystem.

Attack Vector

The attack is conducted remotely over the network by sending specially crafted HTTP requests to the vulnerable httpd service. An attacker manipulates URL paths or request parameters to include directory traversal sequences (e.g., ../ or encoded variants) that bypass the intended file access restrictions. No authentication is required to exploit this vulnerability.

The vulnerability allows unauthorized file access by exploiting the path handling weakness in R7WebsSecurityHandlerfunction. Attackers typically target sensitive system files such as configuration files, password databases, or firmware-related files. For detailed technical information regarding the exploit methodology, refer to the GitHub Vulnerability Repository and the VulDB Vulnerability Entry #356515.

Detection Methods for CVE-2026-5962

Indicators of Compromise

• HTTP requests to the Tenda CH22 web interface containing directory traversal sequences such as ../, ..%2f, or %2e%2e/ in URL paths or parameters
• Unexpected access attempts to system files like /etc/passwd, configuration files, or other sensitive paths outside the web root
• Anomalous HTTP traffic patterns targeting the httpd service with path manipulation attempts
• Log entries showing successful file access to directories outside the normal web application scope

Detection Strategies

• Deploy web application firewall (WAF) rules to detect and block HTTP requests containing path traversal sequences targeting Tenda devices
• Configure intrusion detection systems (IDS) to alert on traffic patterns consistent with directory traversal exploitation attempts against embedded device web interfaces
• Monitor network traffic for suspicious HTTP requests to Tenda CH22 devices containing encoded or double-encoded traversal sequences
• Implement network segmentation to isolate IoT devices like routers and monitor cross-segment access attempts

Monitoring Recommendations

• Enable and regularly review HTTP access logs on the Tenda CH22 device if available
• Deploy network monitoring solutions to capture and analyze traffic destined for embedded device management interfaces
• Set up alerts for unusual file access patterns or authentication failures on network infrastructure devices
• Conduct regular vulnerability scans of IoT and network devices to identify exposed management interfaces

How to Mitigate CVE-2026-5962

Immediate Actions Required

• Restrict network access to the Tenda CH22 web management interface to trusted IP addresses only using firewall rules
• Disable remote administration features if not required and limit access to local network only
• Place the affected device behind a properly configured firewall that can filter malicious requests
• Monitor for firmware updates from Tenda that address this vulnerability

Patch Information

At the time of publication, no official patch from Tenda has been confirmed for this vulnerability. Users should monitor the Tenda Official Website for firmware updates addressing CVE-2026-5962. Additionally, consult the VulDB Submission #791277 and VulDB CTI Entry for ongoing updates regarding remediation options.

Workarounds

• Implement network-level access controls to restrict access to the device's web management interface from untrusted networks
• Use a reverse proxy or web application firewall configured to filter requests containing path traversal patterns before they reach the device
• Disable the httpd web service entirely if remote management is not required, and use alternative management methods
• Consider replacing affected devices with hardware that receives regular security updates if no patch becomes available

# Example firewall rule to restrict access to Tenda CH22 management interface
# Allow only trusted management subnet to access the device web interface
iptables -A FORWARD -d <TENDA_CH22_IP> -p tcp --dport 80 -s <TRUSTED_MGMT_SUBNET> -j ACCEPT
iptables -A FORWARD -d <TENDA_CH22_IP> -p tcp --dport 80 -j DROP