CVE-2024-51315 Overview
CVE-2024-51315 is a stack-based buffer overflow in the Tenda TX9 router firmware version V22.03.02.20. The flaw resides in the sub_425964 function invoked by the /goform/SetOnlineDevName HTTP handler. An unauthenticated attacker on the network can send a crafted request that overflows a fixed-size stack buffer, corrupting saved return data and enabling arbitrary code execution on the device. The weakness is classified under [CWE-121: Stack-based Buffer Overflow].
Critical Impact
Remote, unauthenticated attackers can achieve code execution with full compromise of confidentiality, integrity, and availability on affected Tenda TX9 routers.
Affected Products
- Tenda TX9 router
- Firmware version V22.03.02.20
- /goform/SetOnlineDevName web management endpoint
Discovery Timeline
- 2026-07-20 - CVE-2024-51315 published to NVD
- 2026-07-21 - Last updated in NVD database
Technical Details for CVE-2024-51315
Vulnerability Analysis
The Tenda TX9 web management interface exposes the /goform/SetOnlineDevName endpoint for renaming devices attached to the router. Requests to this endpoint are dispatched into the internal function sub_425964, which processes attacker-controlled parameters such as the mac value. The function copies input into a stack-allocated buffer without validating the length of the incoming data. When the supplied value exceeds the destination buffer, adjacent stack memory including the saved return address is overwritten.
Because the endpoint is reachable over the network and requires no authentication in the vulnerable firmware, an attacker on the LAN, or on the WAN when remote management is enabled, can trigger the overflow with a single HTTP request. Successful exploitation yields code execution in the context of the router's web service, typically running with root privileges on embedded Linux firmware.
Root Cause
The root cause is missing bounds checking on user-supplied string parameters before they are copied into a fixed-size stack buffer inside sub_425964. The function relies on unbounded string operations, so any input longer than the destination buffer overwrites saved registers and the return address.
Attack Vector
Exploitation requires network access to the router's HTTP administration interface. The attacker issues a POST request to /goform/SetOnlineDevName containing an oversized mac field. No user interaction or credentials are needed. Public technical analysis is available in the Gitee IoT Vulnerability Report.
// No verified public exploit code is referenced here.
// See the Gitee advisory for reverse-engineering details of sub_425964
// and the overflow triggered via the /goform/SetOnlineDevName mac parameter.
Detection Methods for CVE-2024-51315
Indicators of Compromise
- HTTP POST requests to /goform/SetOnlineDevName containing abnormally long mac parameter values.
- Unexpected reboots, watchdog resets, or httpd crashes on Tenda TX9 devices.
- Outbound connections from the router to unfamiliar hosts, indicating post-exploitation implants.
Detection Strategies
- Inspect network traffic to router management interfaces for /goform/SetOnlineDevName requests with parameter lengths exceeding typical MAC address size.
- Deploy IDS/IPS signatures that flag oversized fields in Tenda goform HTTP handlers.
- Baseline administrative traffic to home and small-office routers and alert on new sources issuing configuration requests.
Monitoring Recommendations
- Log all access to the router web UI at the network edge and forward logs to a central analytics platform.
- Monitor for firmware integrity changes, new listening ports, or unexpected processes on the router where remote telemetry is available.
- Track CVE feeds and vendor advisories for updated Tenda TX9 firmware releases.
How to Mitigate CVE-2024-51315
Immediate Actions Required
- Restrict access to the router web management interface to trusted management VLANs or hosts only.
- Disable remote (WAN-side) management on the Tenda TX9 until a fixed firmware is available.
- Segment vulnerable routers away from sensitive assets and monitor them as untrusted network devices.
Patch Information
No vendor-confirmed patched firmware version is referenced in the current advisory data. Check the Tenda Firmware Download Page for updates addressing CVE-2024-51315 and apply the latest available firmware for the TX9 platform.
Workarounds
- Block inbound access to TCP ports serving the router HTTP administration interface from untrusted networks.
- Place the router behind an upstream firewall that filters unsolicited requests to /goform/ endpoints.
- Replace the device with a supported model if no patched firmware becomes available.
# Example: block WAN-side access to router admin interface using iptables on an upstream gateway
iptables -A FORWARD -i wan0 -d <router_lan_ip> -p tcp --dport 80 -j DROP
iptables -A FORWARD -i wan0 -d <router_lan_ip> -p tcp --dport 443 -j DROP
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
