CVE-2026-2962: D-Link DWR-M960 Buffer Overflow Vulnerability

CVE-2026-2962 Overview

A stack-based buffer overflow vulnerability has been discovered in the D-Link DWR-M960 mobile router running firmware version 1.01.07. This vulnerability exists in the function sub_460F30 within the file /boafrm/formDateReboot, which is part of the Scheduled Reboot Configuration Endpoint. The flaw can be exploited by manipulating the submit-url argument, allowing remote attackers to trigger a buffer overflow condition that could lead to denial of service or potentially arbitrary code execution.

Critical Impact

Remote attackers with low-privilege access can exploit this stack-based buffer overflow vulnerability to potentially execute arbitrary code or crash the device, compromising network security and availability.

Affected Products

• D-Link DWR-M960 Firmware version 1.01.07
• D-Link DWR-M960 Hardware revision B1
• D-Link DWR-M960 Mobile Router

Discovery Timeline

• 2026-02-23 - CVE-2026-2962 published to NVD
• 2026-02-23 - Last updated in NVD database

Technical Details for CVE-2026-2962

Vulnerability Analysis

This vulnerability is classified as a stack-based buffer overflow (CWE-119: Improper Restriction of Operations within the Bounds of a Memory Buffer). The flaw resides in the sub_460F30 function that handles the Scheduled Reboot Configuration functionality. When processing the submit-url parameter through the /boafrm/formDateReboot endpoint, the application fails to properly validate the length of user-supplied input before copying it into a fixed-size stack buffer.

The vulnerability is network-accessible and can be exploited remotely by authenticated users with low privileges. No user interaction is required for exploitation, making this a significant security concern for deployed devices.

Root Cause

The root cause of this vulnerability is improper input validation and the absence of bounds checking when handling the submit-url parameter. The sub_460F30 function copies user-controlled data directly into a stack-allocated buffer without verifying that the input length does not exceed the buffer's capacity. This classic memory safety issue allows attackers to overwrite adjacent stack memory, including return addresses and other critical data structures.

Attack Vector

The attack is conducted remotely over the network by sending a specially crafted HTTP request to the /boafrm/formDateReboot endpoint with an oversized submit-url parameter. An attacker with valid credentials (low privilege access) can submit malformed input designed to overflow the stack buffer. By carefully crafting the payload, the attacker may be able to overwrite the function's return address and redirect execution to attacker-controlled code, or simply crash the device causing denial of service.

The exploit methodology involves submitting a malicious POST request to the Scheduled Reboot Configuration endpoint with an excessively long submit-url value that exceeds the expected buffer size, causing stack corruption. Additional technical details can be found in the GitHub Issue Report and the VulDB entry.

Detection Methods for CVE-2026-2962

Indicators of Compromise

• Unusual HTTP POST requests to /boafrm/formDateReboot containing abnormally long submit-url parameters
• Device crashes or unexpected reboots without scheduled maintenance
• Web server logs showing requests with payload sizes significantly larger than normal for reboot configuration endpoints
• Memory access violations or segmentation faults in device system logs

Detection Strategies

• Implement network intrusion detection rules to flag HTTP requests to /boafrm/formDateReboot with submit-url parameters exceeding expected lengths
• Monitor D-Link DWR-M960 devices for unexpected restarts or service interruptions that may indicate exploitation attempts
• Deploy web application firewall rules to inspect and block requests with oversized parameters targeting the affected endpoint
• Review device access logs for authentication followed by immediate requests to the Scheduled Reboot Configuration endpoint

Monitoring Recommendations

• Enable verbose logging on D-Link DWR-M960 devices to capture detailed request information
• Implement network traffic analysis to detect anomalous patterns targeting router management interfaces
• Set up alerts for device unavailability that could indicate successful denial of service exploitation
• Regularly audit authenticated sessions and correlate with requests to sensitive configuration endpoints

How to Mitigate CVE-2026-2962

Immediate Actions Required

• Restrict network access to the router's management interface to trusted IP addresses only
• Implement strong authentication and limit administrative access to essential personnel
• Place affected D-Link DWR-M960 devices behind a firewall that can filter malicious requests
• Monitor for firmware updates from D-Link and apply patches immediately when available

Patch Information

At the time of publication, no official patch has been released by D-Link for this vulnerability. Organizations should monitor the D-Link Official Website for security advisories and firmware updates. The vulnerability has been publicly documented in VulDB and a detailed GitHub Issue Report is available.

Workarounds

• Disable remote management access and only allow local administration of the device
• Implement network segmentation to isolate the DWR-M960 from untrusted network segments
• Configure access control lists (ACLs) to restrict which hosts can communicate with the router's management interface
• Consider replacing affected devices with alternative hardware if critical security requirements cannot be met

# Example: Restrict management interface access via firewall rules
# Block external access to the vulnerable endpoint
iptables -A INPUT -p tcp --dport 80 -s !192.168.1.0/24 -j DROP
iptables -A INPUT -p tcp --dport 443 -s !192.168.1.0/24 -j DROP

# Allow only trusted management hosts
iptables -A INPUT -p tcp --dport 80 -s 192.168.1.100 -j ACCEPT
iptables -A INPUT -p tcp --dport 443 -s 192.168.1.100 -j ACCEPT