CVE-2025-8958 Overview
CVE-2025-8958 is a stack-based buffer overflow vulnerability in the Tenda TX3 wireless router running firmware version 16.03.13.11_multi_TDE01. The flaw resides in the /goform/fast_setting_wifi_set endpoint, where the ssid parameter is processed without proper bounds checking. Attackers can trigger the overflow remotely over the network. The exploit details have been publicly disclosed, increasing the risk of opportunistic attacks against exposed devices. The vulnerability is categorized under [CWE-119] (Improper Restriction of Operations within the Bounds of a Memory Buffer).
Critical Impact
Remote attackers with low privileges can corrupt stack memory on Tenda TX3 routers by supplying an oversized ssid value, potentially leading to arbitrary code execution or device compromise.
Affected Products
- Tenda TX3 router (hardware)
- Tenda TX3 firmware version 16.03.13.11_multi_TDE01
- Deployments exposing the web management interface to untrusted networks
Discovery Timeline
- 2025-08-14 - CVE-2025-8958 published to NVD
- 2025-10-21 - Last updated in NVD database
Technical Details for CVE-2025-8958
Vulnerability Analysis
The vulnerability exists in the HTTP handler servicing the /goform/fast_setting_wifi_set endpoint of the Tenda TX3 router's web administration interface. This endpoint is part of the initial Wi-Fi configuration workflow and accepts user-supplied parameters, including the wireless network identifier (ssid). The handler copies the attacker-controlled ssid value into a fixed-size stack buffer without enforcing a length limit. Supplying an oversized string overflows the destination buffer and corrupts adjacent stack data, including saved return addresses.
Successful exploitation can lead to arbitrary code execution in the context of the router's web service, which typically runs with elevated privileges on embedded Linux. Outcomes include denial of service, persistent device compromise, traffic interception, and pivoting into the internal network.
Root Cause
The root cause is the absence of input length validation before performing a memory copy operation on the ssid parameter. The function relies on unsafe string handling routines such as strcpy or sprintf rather than bounded equivalents. This is a classic [CWE-119] memory safety failure common in consumer SOHO router firmware.
Attack Vector
An attacker reachable over the network sends a crafted HTTP POST request to /goform/fast_setting_wifi_set containing an ssid field longer than the expected buffer size. Authentication requirements are minimal, and no user interaction is needed. Devices that expose the management interface to the WAN are exposed to internet-based exploitation, while LAN-only deployments remain reachable from any compromised host on the local network.
No verified public proof-of-concept code is available in this dataset. Refer to the GitHub Issue Discussion and VulDB CTI ID #319927 for additional technical context.
Detection Methods for CVE-2025-8958
Indicators of Compromise
- HTTP POST requests to /goform/fast_setting_wifi_set containing abnormally long ssid parameter values
- Unexpected reboots, watchdog resets, or web service crashes on Tenda TX3 devices
- Configuration changes to wireless settings that were not initiated by an administrator
- Outbound traffic from the router to unfamiliar hosts following suspicious management requests
Detection Strategies
- Inspect web server and reverse proxy logs for POST /goform/fast_setting_wifi_set requests originating from untrusted sources
- Apply network IDS signatures that flag HTTP request bodies where the ssid field exceeds typical 32-byte SSID limits
- Correlate router crash events with preceding HTTP requests to identify exploitation attempts
Monitoring Recommendations
- Forward router syslog and management interface access logs to a centralized SIEM for analysis
- Alert on access to administrative endpoints from outside expected management networks
- Monitor for repeated authentication attempts followed by access to fast_setting_wifi_set from the same source
How to Mitigate CVE-2025-8958
Immediate Actions Required
- Restrict access to the Tenda TX3 web management interface to trusted LAN segments only and disable remote (WAN) administration
- Place affected devices behind a firewall and block inbound HTTP/HTTPS access to the router from untrusted networks
- Rotate administrative credentials and audit current router configuration for unauthorized changes
- Inventory all Tenda TX3 devices running firmware 16.03.13.11_multi_TDE01 across the environment
Patch Information
At the time of this writing, no vendor patch is referenced in the available advisory data. Monitor the Tenda Official Site for firmware updates addressing CVE-2025-8958. Until a fix is released, treat affected devices as exposed and apply compensating controls described below.
Workarounds
- Disable the fast Wi-Fi setup workflow if the device configuration allows it
- Segment the router's management VLAN from general user and guest networks
- Replace internet-exposed Tenda TX3 devices with patched hardware where business requirements demand WAN-side management
- Apply ACLs on upstream network equipment to permit management traffic only from designated administrator IPs
# Example upstream ACL restricting access to the router management interface
# Replace ROUTER_IP and ADMIN_HOST with environment-specific values
iptables -A FORWARD -p tcp -d ROUTER_IP --dport 80 -s ADMIN_HOST -j ACCEPT
iptables -A FORWARD -p tcp -d ROUTER_IP --dport 80 -j DROP
iptables -A FORWARD -p tcp -d ROUTER_IP --dport 443 -s ADMIN_HOST -j ACCEPT
iptables -A FORWARD -p tcp -d ROUTER_IP --dport 443 -j DROP
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
