CVE-2024-9533: D-Link DIR-605L Buffer Overflow Vulnerability

CVE-2024-9533 Overview

CVE-2024-9533 is a buffer overflow vulnerability in the D-Link DIR-605L router running firmware version 2.13B01 BETA. The flaw resides in the formDeviceReboot function of /goform/formDeviceReboot, where the next_page argument is not properly bounded before being copied into a fixed-size buffer. An authenticated remote attacker can send a crafted HTTP request to overflow the buffer, potentially corrupting memory and executing arbitrary code on the device. The vulnerability is tracked as [CWE-120] (Classic Buffer Overflow) and has been publicly disclosed with proof-of-concept details available on GitHub.

Critical Impact
Remote attackers with low privileges can trigger memory corruption in the router's web management interface, leading to potential code execution or persistent denial of service on affected D-Link DIR-605L devices.

Affected Products

D-Link DIR-605L router (hardware)
D-Link DIR-605L firmware version 2.13B01 BETA
Deployments exposing the /goform/formDeviceReboot endpoint to untrusted networks

Discovery Timeline

2024-10-05 - CVE-2024-9533 published to NVD
2026-06-17 - Last updated in NVD database

Technical Details for CVE-2024-9533

Vulnerability Analysis

The vulnerability is a classic stack or heap buffer overflow ([CWE-120]) in the DIR-605L web administration interface. The formDeviceReboot handler processes the next_page HTTP parameter, which is intended to indicate the URL to redirect to after a reboot action. The handler copies attacker-controlled input into a fixed-size buffer without validating the length of the supplied data.

Because the DIR-605L is a consumer-grade small office / home office (SOHO) router, the web server typically runs with elevated privileges on the embedded Linux system. Successful exploitation can therefore result in full compromise of the device, giving an attacker control over routing, DNS, and traffic inspection for every client on the network.

Root Cause

The root cause is the absence of bounds checking on the next_page query argument before it is passed to a string copy operation inside formDeviceReboot. Standard unsafe C string handling functions such as strcpy or sprintf are common culprits in D-Link goform binaries and are consistent with the [CWE-120] classification.

Attack Vector

Exploitation requires network reachability to the router's HTTP management interface and low-level authenticated access. The attacker submits a POST or GET request to /goform/formDeviceReboot with an oversized next_page value. The oversized value overwrites adjacent memory on the web daemon's stack or heap, and a crafted payload can redirect execution flow. Additional technical details and a proof-of-concept are documented in the public GitHub PoC for D-Link DIR-605L and the VulDB CVE-279239 Information entry.

No verified exploit code is reproduced here. See the referenced VulDB #279239 advisory for technical write-up.

Detection Methods for CVE-2024-9533

Indicators of Compromise

HTTP requests to /goform/formDeviceReboot containing unusually long next_page parameter values, especially strings exceeding a few hundred bytes.
Unexpected reboots or web daemon crashes on DIR-605L devices, followed by loss of management access.
Configuration changes on the router (DNS server, administrative password, remote management settings) that were not initiated by an administrator.

Detection Strategies

Inspect network flows and web application firewall logs for POST/GET requests to /goform/formDeviceReboot with oversized query parameters.
Correlate router syslog output with authentication events to identify suspicious sessions preceding reboot events.
Monitor DHCP and DNS behavior on segments served by DIR-605L devices for signs of routing or DNS tampering.

Monitoring Recommendations

Forward router syslog, DHCP, and DNS telemetry to a centralized SIEM for retention and query.
Baseline normal administrative activity on the router web interface so anomalous formDeviceReboot requests stand out.
Alert on repeated crashes or watchdog resets of the httpd process on affected devices.

How to Mitigate CVE-2024-9533

Immediate Actions Required

Disable remote (WAN-side) administration on all DIR-605L devices immediately.
Restrict LAN-side access to the router web interface to a dedicated management VLAN or trusted management workstation.
Enforce strong administrator credentials and rotate any passwords that may have been exposed.
Inventory the environment for DIR-605L units running firmware 2.13B01 BETA and schedule replacement where a patched firmware is not available.

Patch Information

At the time of publication, no vendor advisory or fixed firmware release is referenced in the NVD entry for CVE-2024-9533. The DIR-605L is an older consumer router and may be past its supported lifecycle. Administrators should consult the D-Link Official Website and D-Link regional security bulletins for end-of-life status and any subsequent firmware updates. If no patched firmware is issued, replacement with a currently supported router platform is the recommended long-term action.

Workarounds

Block inbound HTTP and HTTPS access to the router's management interface from the WAN using upstream firewall rules.
Place the router's management interface behind an ACL that permits only known management hosts.
Segment untrusted clients (guest Wi-Fi, IoT devices) away from any network segment that can reach the router's administrative interface.
Where feasible, replace end-of-life DIR-605L hardware with a vendor-supported device that receives active security updates.

bash

# Example upstream firewall rule to block WAN access to the router web UI
# (adjust interface and router IP for your environment)
iptables -A FORWARD -i wan0 -p tcp -d 192.0.2.1 --dport 80  -j DROP
iptables -A FORWARD -i wan0 -p tcp -d 192.0.2.1 --dport 443 -j DROP

# Restrict LAN access to router admin UI to a single management host
iptables -A FORWARD -s 10.0.0.0/24 ! -s 10.0.0.10 -d 192.0.2.1 --dport 80 -j DROP