CVE-2026-2960 Overview
A critical stack-based buffer overflow vulnerability has been discovered in D-Link DWR-M960 wireless routers running firmware version 1.01.07. The vulnerability exists in the function sub_468D64 within the file /boafrm/formDhcpv6s, where improper handling of the submit-url argument allows remote attackers to execute arbitrary code or cause denial of service conditions. The exploit has been publicly disclosed and proof-of-concept code may be available.
Critical Impact
Remote attackers can exploit this stack-based buffer overflow to potentially gain complete control over affected D-Link DWR-M960 routers, compromising network security and enabling further attacks on connected devices.
Affected Products
- D-Link DWR-M960 Firmware version 1.01.07
- D-Link DWR-M960 Hardware revision B1
- D-Link DWR-M960 series wireless routers
Discovery Timeline
- 2026-02-23 - CVE-2026-2960 published to NVD
- 2026-02-23 - Last updated in NVD database
Technical Details for CVE-2026-2960
Vulnerability Analysis
This vulnerability is classified under CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer), indicating that the affected function fails to properly validate the size of input data before copying it to a fixed-size stack buffer. The vulnerable code path exists in the DHCPv6 server configuration handler, which processes form submissions without adequate bounds checking on the submit-url parameter.
When a specially crafted HTTP request is sent to the /boafrm/formDhcpv6s endpoint with an overly long submit-url value, the data overflows the allocated stack buffer. This can overwrite adjacent stack memory including saved return addresses, potentially allowing an attacker to redirect program execution to attacker-controlled code.
Root Cause
The root cause of this vulnerability is insufficient input validation in the sub_468D64 function. The function accepts the submit-url argument from user-supplied form data and copies it into a stack-allocated buffer without verifying that the input length does not exceed the buffer's capacity. This classic buffer overflow pattern in embedded firmware results from:
- Missing length checks on the submit-url parameter
- Use of unsafe string handling functions that do not enforce buffer boundaries
- Lack of stack canary protection or other memory corruption mitigations in the firmware
Attack Vector
The attack can be executed remotely over the network. An attacker with low-privilege access to the router's web interface can submit a maliciously crafted HTTP POST request to the vulnerable endpoint. The attack requires:
- Network access to the router's administrative interface (typically on the LAN or exposed WAN interface)
- Authentication with low-privilege credentials (or exploitation when authentication is misconfigured)
- Sending an HTTP POST request to /boafrm/formDhcpv6s with an oversized submit-url parameter
The vulnerability is exploited by sending a payload that overflows the stack buffer, overwrites the return address, and redirects execution to shellcode or ROP gadgets. Additional technical details can be found in the GitHub Issue Discussion and VulDB Entry #347327.
Detection Methods for CVE-2026-2960
Indicators of Compromise
- Unexpected HTTP POST requests to /boafrm/formDhcpv6s with unusually large submit-url parameters
- Router crashes, reboots, or unresponsive behavior without administrative action
- Anomalous outbound network connections originating from the router device
- Modified firmware configurations or unauthorized administrative accounts
Detection Strategies
- Monitor HTTP traffic to router administrative interfaces for POST requests to /boafrm/formDhcpv6s containing parameter values exceeding normal length thresholds
- Implement network intrusion detection rules to identify buffer overflow attack patterns targeting D-Link router endpoints
- Review router access logs for repeated failed authentication attempts followed by exploitation attempts
- Deploy firmware integrity monitoring to detect unauthorized modifications
Monitoring Recommendations
- Enable logging on the router's administrative interface and forward logs to a centralized SIEM
- Configure network monitoring to alert on large HTTP POST bodies directed at router management ports
- Implement network segmentation to restrict access to router administrative interfaces from untrusted network segments
How to Mitigate CVE-2026-2960
Immediate Actions Required
- Restrict access to the router's administrative interface to trusted IP addresses only using firewall rules
- Disable remote administration from the WAN interface if not required
- Verify firmware version and check D-Link support resources for updated firmware
- Monitor for unusual router behavior indicating potential compromise
Patch Information
At the time of publication, D-Link has not released an official security advisory or patch for this vulnerability. Administrators should monitor the D-Link Security Resources page for firmware updates addressing CVE-2026-2960. Given the end-of-life status of some D-Link products, replacement with supported hardware may be necessary if no patch becomes available.
For additional vulnerability details and tracking, refer to VulDB CTI ID #347327.
Workarounds
- Disable the DHCPv6 server functionality if not required for network operations
- Implement network-level access controls (ACLs) to limit administrative interface access to specific management workstations
- Place the router behind a firewall that can filter malicious requests to the vulnerable endpoint
- Consider replacing vulnerable hardware with devices from vendors that provide ongoing security support
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
