CVE-2024-9552 Overview
CVE-2024-9552 is a buffer overflow vulnerability in the D-Link DIR-605L router running firmware version 2.13B01 BETA. The flaw resides in the formSetWanNonLogin function handling requests to /goform/formSetWanNonLogin. An attacker who manipulates the webpage argument can trigger a buffer overflow condition. The issue is classified under CWE-120 (Buffer Copy without Checking Size of Input). The exploit has been disclosed publicly, increasing the risk of opportunistic attacks against exposed devices. The DIR-605L is a legacy consumer router, and D-Link has ended support for many affected models in this product line.
Critical Impact
Remote attackers with low privileges can trigger a buffer overflow on the DIR-605L, potentially leading to arbitrary code execution or denial of service on the router.
Affected Products
- D-Link DIR-605L router (hardware)
- D-Link DIR-605L firmware version 2.13B01 BETA
- Legacy D-Link consumer networking equipment reaching end-of-life status
Discovery Timeline
- 2024-10-06 - CVE-2024-9552 published to the National Vulnerability Database
- 2026-06-17 - Last updated in NVD database
Technical Details for CVE-2024-9552
Vulnerability Analysis
The vulnerability affects the formSetWanNonLogin request handler in the DIR-605L web administration interface. The handler processes the webpage parameter without validating its length before copying it into a fixed-size buffer. This unchecked copy operation allows attacker-supplied data to overwrite adjacent memory. On embedded MIPS-based routers such as the DIR-605L, buffer overflows in HTTP form handlers frequently overwrite saved return addresses on the stack, enabling control-flow hijacking. The attack is executed over the network against the router's HTTP interface and requires only low-level authentication according to the published vector. Successful exploitation impacts confidentiality, integrity, and availability of the device.
Root Cause
The root cause is the absence of bounds checking on the webpage argument before it is written into a stack or heap buffer inside formSetWanNonLogin. The handler trusts the length of user-supplied HTTP form data, a common pattern in legacy embedded web servers derived from goahead or boa. Refer to the GitHub Vulnerability Documentation for the disassembly and parameter details.
Attack Vector
An attacker sends a crafted HTTP POST request to /goform/formSetWanNonLogin on the router's management interface with an oversized webpage parameter. If the interface is exposed to the WAN, or if the attacker has any foothold on the LAN, the request can be delivered remotely. The overflow can cause the httpd process to crash (denial of service) or, with a properly staged payload, redirect execution to attacker-controlled code. See the VulDB entry #279350 for additional technical references.
Detection Methods for CVE-2024-9552
Indicators of Compromise
- HTTP POST requests to /goform/formSetWanNonLogin containing an unusually long webpage parameter
- Repeated crashes or restarts of the router's httpd process visible in device logs
- Unexpected WAN configuration changes on the DIR-605L administrative interface
- Outbound connections from the router to unknown IP addresses following suspicious HTTP traffic
Detection Strategies
- Inspect network traffic destined for router management interfaces for oversized form parameters targeting /goform/ endpoints
- Deploy network intrusion detection signatures that flag formSetWanNonLogin requests exceeding expected parameter lengths
- Correlate HTTP traffic to router IPs with subsequent DNS or routing anomalies indicating device compromise
Monitoring Recommendations
- Monitor router syslog output, where available, for repeated authentication failures and process crashes
- Track DHCP and DNS behavior of the router for unexpected changes, which often follow router firmware compromise
- Review firewall logs for inbound connections to router management ports (TCP/80, TCP/443) from untrusted sources
How to Mitigate CVE-2024-9552
Immediate Actions Required
- Disable remote WAN-side administration on the DIR-605L to eliminate internet-based exposure of the vulnerable endpoint
- Restrict LAN-side access to the router's management interface to trusted administrative hosts only
- Change default administrative credentials and enforce strong passwords to raise the bar for the required low-privilege access
- Plan replacement of the DIR-605L with a currently supported router model
Patch Information
D-Link has not published a fixed firmware release for CVE-2024-9552 in the referenced advisories. The DIR-605L is a legacy product, and users should consult the D-Link Official Website and regional support pages for end-of-life status. Where no vendor patch is available, replacement of the affected hardware is the recommended remediation.
Workarounds
- Segment the router onto a management VLAN accessible only from an administrative workstation
- Block inbound WAN traffic to router management ports at an upstream firewall
- Disable any port-forwarding rules that expose the router's HTTP interface to the internet
- Replace the DIR-605L with a router receiving active security updates as the long-term mitigation
# Example: block external access to router management interface at the upstream firewall
iptables -A FORWARD -p tcp --dport 80 -d <router-ip> -i <wan-interface> -j DROP
iptables -A FORWARD -p tcp --dport 443 -d <router-ip> -i <wan-interface> -j DROP
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
