CVE-2026-82592: D-Link DIR-825M Buffer Overflow Vulnerability

CVE-2026-82592 Overview

CVE-2026-82592 is a stack-based buffer overflow vulnerability in the D-Link DIR-825M router running firmware version 1.1.8. The flaw resides in the sub_46725C function within /boafrm/formDiskFormat, the Disk Formatting Handler Endpoint. Attackers can trigger the overflow by manipulating the partition argument in HTTP requests sent to the web management interface. The issue is remotely exploitable, and a public exploit is available. The vulnerability is classified under CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer).

Critical Impact
Remote attackers with low-privileged access can corrupt router memory, potentially achieving arbitrary code execution or denial of service on affected D-Link DIR-825M devices.

Affected Products

D-Link DIR-825M router, firmware version 1.1.8
formDiskFormat component (Disk Formatting Handler Endpoint)
sub_46725C function processing the partition parameter

Discovery Timeline

2026-08-30 - CVE-2026-82592 published to NVD
2026-08-31 - Last updated in NVD database

Technical Details for CVE-2026-82592

Vulnerability Analysis

The vulnerability exists in the HTTP request handler responsible for disk formatting operations on the D-Link DIR-825M router. When a client submits a request to /boafrm/formDiskFormat, the function sub_46725C processes the partition parameter without validating the input length. The parameter value is copied into a fixed-size stack buffer, allowing an attacker to overwrite adjacent stack memory including saved return addresses.

Exploitation requires network reachability to the router's web interface and authenticated access at a low privilege level. Once triggered, the overflow can corrupt control-flow structures on the stack. On MIPS-based embedded systems such as the DIR-825M, this typically enables attackers to hijack execution and run arbitrary shellcode with the privileges of the web server process. Successful exploitation can result in full compromise of the device and pivoting into the connected network.

Root Cause

The root cause is missing bounds checking on the partition argument before it is copied into a stack-allocated buffer. The handler trusts the length of user-supplied form data, which violates safe input-handling practices for network-facing services and matches the [CWE-119] classification.

Attack Vector

The attack is delivered over the network by sending a crafted HTTP POST request to the /boafrm/formDiskFormat endpoint with an oversized partition value. The exploit is publicly available, lowering the barrier for opportunistic attackers. Technical proof-of-concept details are documented in the GitHub IoT Vulnerability Report and the VulDB entry for CVE-2026-82592.

No synthetic exploitation code is provided here. Refer to the referenced advisories for technical reproduction details.

Detection Methods for CVE-2026-82592

Indicators of Compromise

HTTP POST requests to /boafrm/formDiskFormat containing an unusually long partition parameter value.
Unexpected reboots, crashes, or httpd/boa process failures on the DIR-825M device.
Outbound connections from the router to unknown hosts following administrative HTTP activity.
New or modified files, cron jobs, or firewall rules on the router that were not applied by an administrator.

Detection Strategies

Inspect network traffic to router management interfaces for requests targeting formDiskFormat with abnormal payload sizes.
Deploy intrusion detection signatures that flag POST requests to /boafrm/formDiskFormat where the partition field exceeds expected length limits.
Correlate router log anomalies with authentication events to identify low-privileged accounts issuing formatting requests.

Monitoring Recommendations

Restrict administrative access to router web interfaces to trusted management VLANs only.
Enable syslog forwarding from the router to a centralized logging platform for retention and correlation.
Alert on repeated failed logins or unusual authenticated activity against the DIR-825M web UI.

How to Mitigate CVE-2026-82592

Immediate Actions Required

Remove the DIR-825M 1.1.8 web management interface from any WAN-facing exposure and block external access.
Restrict LAN access to the router administration page to a limited set of trusted management hosts.
Rotate administrative credentials and disable any low-privileged accounts that are not strictly required.
Monitor traffic to /boafrm/formDiskFormat and investigate any anomalous requests.

Patch Information

No vendor patch is referenced in the CVE record at the time of publication. Consult the D-Link official website for firmware updates and end-of-life notices. If the DIR-825M model is no longer supported, plan a migration to a currently supported router platform.

Workarounds

Disable remote management on the WAN interface of the DIR-825M.
Place the device behind a network segment that enforces ACLs restricting HTTP access to the management interface.
Replace end-of-life D-Link DIR-825M hardware with a vendor-supported router that receives active firmware updates.

bash

# Example ACL concept restricting router admin UI to a management subnet
# (apply on an upstream firewall, not on the vulnerable device itself)
allow tcp from 10.0.10.0/24 to <router_ip> port 80
deny  tcp from any to <router_ip> port 80