CVE-2025-46631 Overview
CVE-2025-46631 affects the Tenda RX2 Pro router running firmware version 16.03.30.14. The vulnerability stems from improper access controls in the device's web management portal. An unauthenticated remote attacker can enable telnet access to the router's underlying operating system by sending a crafted request to the /goform/telnet endpoint.
The issue is classified under [CWE-287] Improper Authentication. Successful exploitation exposes an interactive shell interface on the device without requiring credentials. This provides a foothold for further exploitation of the router's operating system and connected network segments.
Critical Impact
Unauthenticated attackers on the network can enable telnet on the router by issuing a single HTTP request, exposing the device OS to interactive access.
Affected Products
- Tenda RX2 Pro router (hardware)
- Tenda RX2 Pro firmware version 16.03.30.14
- Web management portal (httpd) component handling /goform/telnet
Discovery Timeline
- 2025-05-01 - CVE-2025-46631 published to NVD
- 2026-06-17 - Last updated in NVD database
Technical Details for CVE-2025-46631
Vulnerability Analysis
The Tenda RX2 Pro exposes an HTTP endpoint at /goform/telnet through the router's httpd web management service. This endpoint invokes a handler that starts the telnetd daemon on the device. The handler does not verify that the requester holds an authenticated administrative session.
An attacker with network access to the management interface can issue the request without credentials. Once telnet is enabled, the attacker can connect to the router's shell over the standard telnet port. This exposes the underlying Linux-based operating system to interactive command execution, subject to whatever account credentials or lack thereof the telnet service enforces.
The vulnerability aligns with the EPSS probability of 5.369% (91.683 percentile), reflecting elevated exploitation likelihood relative to typical CVEs.
Root Cause
The root cause is a missing authentication check in the /goform/telnet request handler. Tenda's web application framework registers form handlers that should validate session cookies or authentication tokens before executing privileged actions. In this case, the telnet activation handler processes requests directly without invoking the authentication routine.
Attack Vector
The attack requires network reachability to the router's web management interface. The attacker sends an HTTP GET or POST request to /goform/telnet on the router's LAN IP or, in misconfigured deployments, its WAN IP. The httpd process processes the request and starts telnetd. The attacker then opens a telnet session to the router on port 23 and interacts with the shell.
No exploit code has been published in the NVD references, but a public writeup describing the request path is available at the uTurn Blog CVE-2025-46631 Writeup.
Detection Methods for CVE-2025-46631
Indicators of Compromise
- HTTP requests targeting /goform/telnet on Tenda RX2 Pro devices from unexpected sources
- Unexpected telnetd process running on the router or open TCP port 23
- Inbound telnet connections to router management IP addresses in firewall or flow logs
- Configuration changes on the router that were not initiated by an administrator
Detection Strategies
- Inspect HTTP access logs on the router for requests to /goform/telnet and correlate with authenticated administrator activity
- Scan the internal network for TCP port 23 exposure on router IP addresses using port scanners
- Monitor DHCP and router management interfaces for unauthorized configuration changes
- Alert on new telnet sessions terminating at network infrastructure devices
Monitoring Recommendations
- Enable NetFlow or equivalent flow logging on network segments containing the router and alert on port 23 traffic
- Configure syslog forwarding from the router to a central log store for retention and analysis
- Baseline expected management traffic and alert on anomalies against the /goform/ URI space
How to Mitigate CVE-2025-46631
Immediate Actions Required
- Restrict access to the router's web management interface to trusted management VLANs only
- Verify the WAN interface does not expose the web management portal to the internet
- Disable telnet on the router and block TCP port 23 at the network perimeter
- Rotate any local credentials on the device and audit for unauthorized configuration changes
Patch Information
No vendor advisory or patched firmware release is listed in the NVD references for CVE-2025-46631 at the time of publication. Refer to the Tenda Official Website for firmware update notifications. Apply firmware updates for the Tenda RX2 Pro as soon as the vendor publishes a fixed release.
Workarounds
- Place the router's management interface on a dedicated administrative VLAN with ACLs restricting HTTP access to known admin hosts
- Block inbound TCP port 23 (telnet) at upstream firewalls and on the router itself where possible
- Replace vulnerable devices with alternative hardware if a vendor patch is not forthcoming and the device is business critical
# Example ACL blocking telnet and restricting router web management
# Block inbound telnet at the perimeter firewall
iptables -A FORWARD -p tcp --dport 23 -j DROP
# Restrict router web UI (port 80/443) to management subnet only
iptables -A FORWARD -p tcp -d <router_ip> --dport 80 ! -s 10.10.10.0/24 -j DROP
iptables -A FORWARD -p tcp -d <router_ip> --dport 443 ! -s 10.10.10.0/24 -j DROP
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
