CVE-2024-9566 Overview
CVE-2024-9566 is a buffer overflow vulnerability in the D-Link DIR-619L B1 firmware version 2.06. The flaw resides in the formDeviceReboot function within /goform/formDeviceReboot. Attackers can trigger the overflow by manipulating the next_page argument in HTTP requests to the router's web interface.
The vulnerability is remotely exploitable and a public exploit has been disclosed. The weakness is classified as [CWE-120] (Buffer Copy without Checking Size of Input). D-Link DIR-619L reached end-of-life status, and the vendor is unlikely to release a security patch for this legacy device.
Critical Impact
Remote attackers with low-privileged access can trigger a buffer overflow in the router's web management interface, potentially leading to arbitrary code execution or denial of service on the affected device.
Affected Products
- D-Link DIR-619L Router (Hardware Revision B1)
- D-Link DIR-619L Firmware version 2.06
- Legacy D-Link SOHO routers sharing the vulnerable formDeviceReboot handler
Discovery Timeline
- 2024-10-07 - CVE-2024-9566 published to NVD
- 2026-06-17 - Last updated in NVD database
Technical Details for CVE-2024-9566
Vulnerability Analysis
The vulnerability affects the formDeviceReboot function in the D-Link DIR-619L B1 2.06 firmware. This function handles HTTP POST requests sent to the /goform/formDeviceReboot endpoint on the router's administrative web server. The handler copies the user-supplied next_page parameter into a fixed-size stack buffer without validating the length of the input.
Attackers who submit an oversized next_page value can overflow the buffer and overwrite adjacent memory, including saved return addresses on the stack. Because the router runs on a MIPS-based embedded Linux platform without modern exploit mitigations such as address space layout randomization or non-executable stack, exploitation can lead to arbitrary code execution under the context of the web server process, which typically runs with root privileges.
Root Cause
The root cause is missing bounds checking on the next_page HTTP parameter before it is copied into a stack-allocated buffer inside formDeviceReboot. The code path uses an unsafe string-copy operation that trusts the length of attacker-controlled input, matching the [CWE-120] pattern of classic buffer overflow flaws in embedded firmware.
Attack Vector
Exploitation requires network access to the router's web management interface and low-privileged authenticated access. An attacker sends a crafted HTTP request to /goform/formDeviceReboot containing an oversized next_page argument. The resulting overflow can crash the device, causing denial of service, or, when combined with careful payload construction, redirect execution to attacker-controlled code.
Public proof-of-concept material is available in the GitHub PoC for D-Link Router and referenced through VulDB Entry #279460. No verified exploitation code is reproduced here; refer to the linked technical references for the underlying request format.
Detection Methods for CVE-2024-9566
Indicators of Compromise
- HTTP POST requests to /goform/formDeviceReboot containing an unusually long next_page parameter value
- Unexpected reboots or crash loops on DIR-619L devices coinciding with inbound web-management traffic
- Web administrative sessions originating from untrusted external IP addresses
- New or unexplained outbound connections from the router to unknown hosts following administrative requests
Detection Strategies
- Inspect network traffic for HTTP requests to /goform/formDeviceReboot and alert when the next_page parameter exceeds a reasonable length threshold
- Monitor router syslog output for watchdog resets, segmentation faults, or repeated httpd process restarts
- Baseline administrative HTTP traffic to the router and flag deviations in request size or source geolocation
Monitoring Recommendations
- Forward router syslog and NetFlow data to a centralized log platform for correlation and retention
- Track authentication events against the router web interface and alert on brute-force patterns
- Continuously verify that router management interfaces are not exposed to the public internet
How to Mitigate CVE-2024-9566
Immediate Actions Required
- Disable remote (WAN-side) administration on affected DIR-619L devices and restrict management access to a trusted internal VLAN
- Change default and shared administrative credentials to strong, unique values to reduce the risk of authenticated exploitation
- Segment the router from sensitive internal networks and place it behind an upstream firewall that filters unsolicited HTTP traffic
- Plan replacement of the DIR-619L with a currently supported router model, as this device is end-of-life
Patch Information
D-Link has not released a security patch for CVE-2024-9566. The DIR-619L B1 is a legacy product and is no longer supported by the vendor. Consult the D-Link Official Website for end-of-life notices and current replacement models. Additional vulnerability metadata is available in VulDB CTI-ID #279460 and the corresponding VulDB Submission #414541.
Workarounds
- Block external access to TCP ports used by the router web interface at the perimeter firewall
- Restrict access to /goform/formDeviceReboot using upstream network ACLs where feasible
- Replace the affected device with a supported router that receives active firmware updates
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
