CVE-2025-2960: TRENDnet TEW-637AP Null Pointer Vulnerability

CVE-2025-2960 Overview

CVE-2025-2960 is a null pointer dereference vulnerability affecting TRENDnet TEW-637AP and TEW-638APB wireless access points running firmware versions 1.2.7 and 1.3.0.106. The flaw resides in the sub_41DED0 function within /bin/goahead, the embedded HTTP request handler that services the device's web management interface. An adjacent-network attacker can send a crafted HTTP request that triggers a null pointer dereference, causing the affected service to crash. The exploit details have been publicly disclosed. TRENDnet was contacted before disclosure but did not respond, and no vendor patch is available.

Critical Impact
An unauthenticated attacker on the local network can crash the HTTP management daemon of affected TRENDnet access points, disrupting device administration and network availability. [CWE-476]

Affected Products

TRENDnet TEW-637AP firmware version 1.2.7
TRENDnet TEW-638APB firmware version 1.3.0.106
Devices exposing the goahead HTTP management service on the local network

Discovery Timeline

2025-03-30 - CVE-2025-2960 published to the National Vulnerability Database
2026-06-17 - Last updated in NVD database

Technical Details for CVE-2025-2960

Vulnerability Analysis

The vulnerability exists in the sub_41DED0 function of the /bin/goahead binary. GoAhead is an embedded web server commonly used in consumer network hardware to expose administrative interfaces. The affected function processes incoming HTTP requests but fails to validate that a required pointer is non-null before dereferencing it. When an attacker submits a crafted request containing missing or malformed fields, the handler dereferences a null pointer and the goahead process crashes. The result is a denial-of-service condition against the device management plane, and depending on how the router supervises the process, it can also degrade routing and wireless services.

Root Cause

The root cause is improper input validation combined with unsafe pointer handling in the HTTP request parser [CWE-476, CWE-404]. Specifically, sub_41DED0 assumes that a pointer returned by an upstream parsing routine is always valid. When a request omits or malforms the expected header or parameter, that pointer is null. The absence of a null check before dereference converts a benign parsing failure into a process crash. No memory corruption or code execution is required.

Attack Vector

Exploitation requires access to the adjacent network, typically the wireless or wired LAN segment where the access point is reachable. Authentication is not required. An attacker sends a single malformed HTTP request to the device's web management interface. The goahead daemon dereferences the null pointer and terminates. Repeated requests can keep the administrative interface offline. Because embedded HTTP servers on consumer devices often share process space with other management functions, the crash can also affect adjacent services.

// No verified proof-of-concept code is published in the referenced advisories.
// Refer to the VulDB entry for technical details: https://vuldb.com/?id.302013

Detection Methods for CVE-2025-2960

Indicators of Compromise

Unexpected restarts or crashes of the goahead process on affected TRENDnet devices
Loss of access to the device's web management interface without administrator action
Malformed HTTP requests from LAN hosts targeting the router's management IP on ports 80 or 8080
Repeated short-lived TCP connections to the management interface from a single source

Detection Strategies

Monitor router syslog output for repeated goahead process termination or watchdog restart events
Inspect LAN-side packet captures for HTTP requests with truncated headers or absent required parameters directed at the router
Baseline normal management traffic and alert on anomalous request patterns to the router's administrative interface

Monitoring Recommendations

Forward device syslog and SNMP traps to a centralized logging platform for correlation with LAN activity
Track availability of the management interface with active health checks and alert on unexpected downtime
Restrict and monitor which internal hosts communicate with router management addresses

How to Mitigate CVE-2025-2960

Immediate Actions Required

Inventory TRENDnet TEW-637AP and TEW-638APB devices and confirm firmware versions 1.2.7 and 1.3.0.106 respectively
Restrict access to the device web management interface to a dedicated management VLAN or specific administrative hosts
Disable remote administration and ensure the management interface is not reachable from untrusted network segments
Consider replacing end-of-life hardware where the vendor is unresponsive to security disclosures

Patch Information

No vendor patch is available. According to the disclosure, TRENDnet was contacted about this issue but did not respond. The TEW-637AP and TEW-638APB are legacy consumer access points that may no longer receive firmware updates. Organizations should treat these devices as unsupported and plan for replacement with a currently supported product.

Workarounds

Segment affected access points onto an isolated network with strict access controls to the management interface
Apply LAN-side firewall rules that permit management traffic only from authorized administrator IP addresses
Replace affected hardware with a supported model that receives active firmware maintenance

bash

# Example: restrict LAN access to the router management interface using iptables on an upstream gateway
# Replace 192.0.2.10 with the router IP and 192.0.2.100 with the authorized admin host
iptables -A FORWARD -s 192.0.2.100 -d 192.0.2.10 -p tcp --dport 80 -j ACCEPT
iptables -A FORWARD -d 192.0.2.10 -p tcp --dport 80 -j DROP