CVE-2025-11408: D-Link DI-7001 Buffer Overflow Vulnerability

CVE-2025-11408 Overview

CVE-2025-11408 is a buffer overflow vulnerability affecting the D-Link DI-7001 MINI router running firmware version 24.04.18B1. The flaw resides in an unspecified function within the /dbsrv.asp endpoint, where manipulation of the str argument triggers memory corruption [CWE-119]. An authenticated attacker can exploit the issue remotely over the network. The exploit has been disclosed publicly, increasing the likelihood of opportunistic abuse against exposed devices.

Critical Impact
Remote attackers with low privileges can corrupt memory on affected D-Link DI-7001 MINI devices, potentially leading to denial of service or arbitrary code execution on edge network equipment.

Affected Products

D-Link DI-7001 MINI hardware revision B1
D-Link DI-7001 MINI-8G firmware version 24.04.18B1
D-Link DI-7001MINI-8G appliances exposing the /dbsrv.asp interface

Discovery Timeline

2025-10-07 - CVE-2025-11408 published to the National Vulnerability Database (NVD)
2025-11-19 - Last updated in NVD database

Technical Details for CVE-2025-11408

Vulnerability Analysis

The vulnerability is a classic buffer overflow rooted in improper restriction of operations within the bounds of a memory buffer [CWE-119]. The affected component is the /dbsrv.asp handler in the DI-7001 MINI web management interface. When a request supplies an oversized value to the str parameter, the server-side routine copies attacker-controlled data into a fixed-size buffer without enforcing length validation.

Successful exploitation can overwrite adjacent memory regions, including return addresses or function pointers on embedded MIPS or ARM platforms commonly used in D-Link routers. The attack requires network reachability to the device management plane and low-level authenticated access. Because the disclosed exploit is public, defenders should treat exposed management interfaces as actively targeted.

Root Cause

The root cause is missing input length validation in the ASP handler responsible for processing the str argument. The function writes user-supplied data into a stack or heap buffer without enforcing a maximum size, allowing memory adjacent to the destination buffer to be overwritten.

Attack Vector

Attackers reach the vulnerability over the network by sending a crafted HTTP request to /dbsrv.asp with an oversized str value. Exploitation requires existing low-privilege credentials on the device but no user interaction. Devices with management interfaces exposed to the internet or untrusted network segments are at elevated risk. Refer to the GitHub issue tracking this CVE and the VulDB entry for technical specifics.

No verified proof-of-concept code is published in the references provided; technical details describe the manipulation of the str parameter sent to the /dbsrv.asp endpoint as the trigger condition.

Detection Methods for CVE-2025-11408

Indicators of Compromise

HTTP POST or GET requests to /dbsrv.asp containing abnormally long str parameter values
Unexpected device reboots, crashes, or httpd process restarts on DI-7001 MINI appliances
Authentication events from unusual source IPs immediately followed by malformed /dbsrv.asp requests
New or modified configuration entries that did not originate from authorized administrators

Detection Strategies

Inspect web server access logs on the router for requests targeting /dbsrv.asp with str payloads exceeding expected length thresholds
Deploy network IDS signatures that flag oversized parameter values directed at D-Link management endpoints
Correlate authentication logs with subsequent administrative HTTP requests to identify low-privileged accounts probing the interface

Monitoring Recommendations

Forward router syslog and HTTP access logs to a centralized SIEM for long-term retention and analytics
Alert on repeated 5xx responses or service restarts on the management plane, which can indicate exploitation attempts
Monitor outbound connections from the router itself, which would be anomalous and may indicate post-exploitation activity

How to Mitigate CVE-2025-11408

Immediate Actions Required

Restrict access to the device management interface to trusted administrative networks only
Disable WAN-side access to the web management interface on all DI-7001 MINI devices
Rotate credentials for all accounts on affected routers and enforce strong, unique passwords
Audit firmware versions across the fleet and inventory all devices running 24.04.18B1

Patch Information

At the time of publication, no vendor patch is referenced in the available advisories. Administrators should monitor the D-Link Security Information portal for firmware updates addressing CVE-2025-11408. If the DI-7001 MINI hardware revision B1 has reached end-of-support, plan replacement with a supported device.

Workarounds

Place the router management interface behind a VPN or jump host accessible only to administrators
Use access control lists (ACLs) on upstream firewalls to block external traffic to the device HTTP/HTTPS management ports
Remove or disable any low-privilege accounts that are not strictly required for operations
Segment the router from untrusted internal networks to reduce the population of potential authenticated attackers

bash

# Example upstream firewall rule restricting access to the router management interface
# Replace ROUTER_IP and ADMIN_SUBNET with environment-specific values
iptables -A FORWARD -p tcp -d ROUTER_IP --dport 80  -s ADMIN_SUBNET -j ACCEPT
iptables -A FORWARD -p tcp -d ROUTER_IP --dport 443 -s ADMIN_SUBNET -j ACCEPT
iptables -A FORWARD -p tcp -d ROUTER_IP --dport 80  -j DROP
iptables -A FORWARD -p tcp -d ROUTER_IP --dport 443 -j DROP