CVE-2025-12274: Tenda CH22 Buffer Overflow Vulnerability

CVE-2025-12274 Overview

CVE-2025-12274 is a buffer overflow vulnerability in Tenda CH22 routers running firmware version 1.0.0.1. The flaw resides in the fromP2pListFilter function handling requests to the /goform/P2pListFilter endpoint. Attackers can trigger the overflow by manipulating the page argument over the network. The issue is classified under [CWE-119] (Improper Restriction of Operations within the Bounds of a Memory Buffer). Public disclosure of the exploit details increases the risk of opportunistic exploitation against exposed devices.

Critical Impact
Remote attackers with low privileges can corrupt memory on affected Tenda CH22 routers, leading to potential denial of service or arbitrary code execution on the device.

Affected Products

Tenda CH22 router (hardware)
Tenda CH22 firmware version 1.0.0.1
Deployments exposing the /goform/P2pListFilter web management endpoint

Discovery Timeline

2025-10-27 - CVE-2025-12274 published to NVD
2025-10-28 - Last updated in NVD database

Technical Details for CVE-2025-12274

Vulnerability Analysis

The vulnerability exists in the fromP2pListFilter handler within the Tenda CH22 web management interface. The handler processes HTTP requests sent to /goform/P2pListFilter and reads the page parameter from the request. The function copies this attacker-controlled input into a fixed-size stack buffer without validating its length. When the supplied value exceeds the buffer capacity, adjacent memory is overwritten.

This class of flaw [CWE-119] is consistent with patterns seen across Tenda SOHO router firmware, where CGI-style handlers parse query string parameters using unsafe string operations. Successful exploitation can corrupt the return address on the stack and redirect execution. The attack requires network access to the device's management interface and only low-level authentication context, making internet-exposed devices especially exposed.

Root Cause

The root cause is missing bounds checking on the page argument before it is copied into a fixed-size local buffer inside fromP2pListFilter. The firmware uses unsafe copy routines that do not enforce a maximum length, allowing the input to overflow the destination buffer and corrupt adjacent stack data, including saved return pointers.

Attack Vector

An attacker reaches the vulnerable code path by sending a crafted HTTP request to /goform/P2pListFilter containing an oversized page parameter. The request can be issued remotely over the network against the router's management interface. Because the exploit has been publicly disclosed, weaponized variants may circulate. Refer to the GitHub CVE Issue Discussion and VulDB #329946 for additional technical context.

Detection Methods for CVE-2025-12274

Indicators of Compromise

HTTP requests to /goform/P2pListFilter containing abnormally long page parameter values
Unexpected reboots, crashes, or watchdog resets of the Tenda CH22 router
Outbound connections from the router to unfamiliar hosts following management-interface traffic
Configuration changes or new firewall rules that were not initiated by an administrator

Detection Strategies

Inspect web server and proxy logs for POST or GET requests to /goform/P2pListFilter with parameter values exceeding expected lengths.
Deploy network IDS rules that flag oversized query string parameters destined for Tenda router management endpoints.
Correlate router crash or reboot events with preceding inbound HTTP requests to the management interface.

Monitoring Recommendations

Forward router syslog and crash telemetry to a centralized logging platform for retention and analysis.
Monitor for management-interface access originating from outside trusted administrative networks.
Track firmware versions across deployed CH22 devices to identify unpatched units requiring remediation.

How to Mitigate CVE-2025-12274

Immediate Actions Required

Remove the Tenda CH22 web management interface from any internet-facing network and restrict it to trusted management VLANs.
Disable remote administration features if they are not strictly required for operations.
Change default and weak administrative credentials to reduce the risk of low-privilege attackers reaching the vulnerable endpoint.
Audit existing devices for signs of the indicators listed above and isolate any device suspected of compromise.

Patch Information

At the time of publication, no vendor advisory or firmware update addressing CVE-2025-12274 has been listed in the NVD references. Administrators should monitor the Tenda Security Overview for an official firmware update for the CH22 product line and apply it as soon as it becomes available.

Workarounds

Place affected routers behind an upstream firewall that blocks unsolicited inbound traffic to the management interface.
Use access control lists to allow management traffic only from designated administrator IP addresses.
Where feasible, replace end-of-support or unpatched CH22 units with currently supported hardware that receives security updates.

bash

# Example iptables rule restricting management access to a trusted admin subnet
iptables -A INPUT -p tcp --dport 80 -s 192.0.2.0/24 -j ACCEPT
iptables -A INPUT -p tcp --dport 80 -j DROP