CVE-2026-7036: Tenda I9 Firmware Path Traversal Flaw

CVE-2026-7036 Overview

A path traversal vulnerability has been identified in Tenda i9 router firmware version 1.0.0.5(2204). This vulnerability affects the R7WebsSecurityHandlerfunction function within the HTTP Handler component, allowing attackers to manipulate file paths and potentially access files outside the intended directory structure. The vulnerability can be exploited remotely over the network without requiring authentication, making it particularly concerning for exposed devices.

Critical Impact

Remote attackers can exploit this path traversal vulnerability to access sensitive files on affected Tenda i9 devices, potentially leading to information disclosure, configuration exposure, or further compromise of the network infrastructure.

Affected Products

• Tenda i9 Firmware version 1.0.0.5(2204)
• Tenda i9 Hardware Device

Discovery Timeline

• 2026-04-26 - CVE-2026-7036 published to NVD
• 2026-04-30 - Last updated in NVD database

Technical Details for CVE-2026-7036

Vulnerability Analysis

This vulnerability is classified as CWE-22 (Improper Limitation of a Pathname to a Restricted Directory), commonly known as path traversal or directory traversal. The flaw exists in the R7WebsSecurityHandlerfunction function within the HTTP Handler component of the Tenda i9 firmware.

Path traversal vulnerabilities occur when user-controlled input is used to construct file paths without proper sanitization or validation. In this case, the HTTP Handler fails to adequately restrict path manipulation, allowing attackers to use sequences such as ../ to traverse outside the intended web root directory. This enables access to arbitrary files on the device's filesystem that the web server process has permission to read.

The network-accessible nature of this vulnerability means that any attacker who can reach the device's HTTP interface can attempt exploitation without requiring any prior authentication.

Root Cause

The root cause of this vulnerability lies in insufficient input validation within the R7WebsSecurityHandlerfunction function. The HTTP Handler component does not properly sanitize or validate user-supplied path information before using it to access filesystem resources. This allows malicious path traversal sequences to bypass intended directory restrictions.

Proper remediation would require implementing robust path canonicalization and validation routines to ensure that all requested paths remain within the designated web root directory, regardless of any traversal sequences included in the request.

Attack Vector

The attack vector for CVE-2026-7036 is network-based, requiring no user interaction or prior authentication. An attacker can craft HTTP requests containing path traversal sequences (such as ../ or URL-encoded equivalents) targeting the vulnerable R7WebsSecurityHandlerfunction function. When the device processes these malicious requests, it may return contents of files outside the intended directory structure.

Successful exploitation could allow attackers to:

• Read sensitive configuration files containing credentials or network settings
• Access system files that reveal device information
• Potentially gather information for further attacks against the device or network

Technical details and exploitation information are publicly available via the GitHub Vulnerability Report and VulDB entry #359616.

Detection Methods for CVE-2026-7036

Indicators of Compromise

• HTTP requests to the Tenda i9 web interface containing path traversal sequences such as ../, ..%2f, or %2e%2e/
• Unusual file access patterns in device logs showing requests for files outside the web root
• HTTP requests targeting the R7WebsSecurityHandlerfunction endpoint with abnormal path parameters
• Unexpected external connections to the device's web management interface

Detection Strategies

• Implement network intrusion detection rules to identify HTTP requests containing common path traversal patterns targeting Tenda i9 devices
• Monitor web server logs for requests with directory traversal sequences or attempts to access sensitive system files
• Deploy web application firewalls (WAF) with rules to block path manipulation attempts
• Use vulnerability scanners to identify exposed Tenda i9 devices running the vulnerable firmware version 1.0.0.5(2204)

Monitoring Recommendations

• Enable and regularly review device access logs for suspicious request patterns
• Monitor network traffic for unauthorized access attempts to Tenda i9 management interfaces
• Implement alerting for any successful file access outside expected web directories
• Track firmware versions across deployed Tenda i9 devices to identify vulnerable installations

How to Mitigate CVE-2026-7036

Immediate Actions Required

• Restrict network access to the Tenda i9 web management interface to trusted IP addresses only
• Place affected devices behind a firewall that blocks external access to the HTTP management port
• Monitor for firmware updates from Tenda that address this vulnerability
• Consider network segmentation to isolate affected devices from sensitive network resources

Patch Information

At the time of publication, no official patch information has been released by Tenda for this vulnerability. Users should monitor the Tenda official website for security updates and firmware releases that address CVE-2026-7036. It is recommended to check vendor resources regularly and apply patches as soon as they become available.

For additional technical details, refer to the VulDB submission #798479 and the GitHub vulnerability report.

Workarounds

• Disable remote management access to the device's web interface if not required
• Implement network-level access controls (ACLs) to restrict access to the device's HTTP interface to trusted management networks only
• Deploy a reverse proxy or WAF in front of the device to filter malicious path traversal attempts
• Consider replacing vulnerable devices with alternative hardware if patches are not forthcoming

# Example: Firewall rule to restrict access to Tenda i9 management interface
# Block external access to device HTTP port (adjust IP and port as needed)
iptables -A INPUT -p tcp --dport 80 -s ! 192.168.1.0/24 -j DROP

# Allow management access only from trusted admin workstation
iptables -A INPUT -p tcp --dport 80 -s 192.168.1.100 -j ACCEPT