CVE-2026-5608
Stack-Based Buffer Overflow in Belkin F9K1122 Remote Form Handler
Publication date: 2026-04-06
Last updated on: 2026-04-30
Assigner: VulDB
Description
Description
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| belkin | f9k1122_firmware | 1.00.33 |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-119 | The product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary. This may result in read or write operations on unexpected memory locations that could be linked to other variables, data structures, or internal program data. |
| CWE-121 | A stack-based buffer overflow condition is a condition where the buffer being overwritten is allocated on the stack (i.e., is a local variable or, rarely, a parameter to a function). |
Attack-Flow Graph
AI Powered Q&A
Can you explain this vulnerability to me?
The vulnerability exists in the Belkin F9K1122 router firmware version 1.00.33, specifically in the formWlanSetup function of the web interface. It involves a stack-based buffer overflow caused by improper handling of the "webpage" parameter. This parameter is copied into a buffer without bounds checking, allowing an attacker to overflow the buffer by sending a specially crafted HTTP POST request to the /goform/formWlanSetup endpoint.
Exploiting this vulnerability can lead to denial of service (DoS) or remote code execution on the affected device.
How can this vulnerability impact me? :
This vulnerability can have serious impacts including causing the router to crash (denial of service) or allowing an attacker to execute arbitrary code remotely. This means an attacker could potentially take control of the affected device, disrupt network connectivity, or use the device as a foothold to attack other systems on the network.
How can this vulnerability be detected on my network or system? Can you suggest some commands?
This vulnerability can be detected by monitoring for suspicious HTTP POST requests sent to the /goform/formWlanSetup endpoint of the Belkin F9K1122 router. Specifically, look for POST requests containing an excessively long or malformed "webpage" parameter, which is used to trigger the stack-based buffer overflow.
A practical detection method is to capture network traffic and filter for POST requests targeting /goform/formWlanSetup with unusually large payloads or parameters.
- Use a network packet capture tool like tcpdump or Wireshark to monitor HTTP POST requests to /goform/formWlanSetup.
- Example tcpdump command to capture relevant traffic: tcpdump -i <interface> -A 'tcp port 80 and (((ip[2:2] - ((ip[0]&0xf)<<2)) - ((tcp[12]&0xf0)>>2)) != 0)' | grep '/goform/formWlanSetup'
- Alternatively, use curl or similar tools to test the endpoint by sending a crafted POST request with a long "webpage" parameter to see if the device responds abnormally.
What immediate steps should I take to mitigate this vulnerability?
Immediate mitigation steps include restricting access to the vulnerable router's web interface to trusted networks only, such as internal LAN segments, to prevent remote exploitation.
Additionally, monitor and block suspicious HTTP POST requests targeting /goform/formWlanSetup, especially those with unusually long "webpage" parameters.
If possible, disable remote management features on the router to reduce exposure.
Since the vendor has not responded with a patch, consider replacing or upgrading the device firmware if a fixed version becomes available.
How does this vulnerability affect compliance with common standards and regulations (like GDPR, HIPAA)?:
The provided information does not specify any direct impact of this vulnerability on compliance with common standards and regulations such as GDPR or HIPAA.