CVE-2026-7101
Buffer Overflow in Tenda F456 HTTPD Allows Remote Exploitation
Publication date: 2026-04-27
Last updated on: 2026-04-29
Assigner: VulDB
Description
Description
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| tenda | f456_firmware | 1.0.0.5 |
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-120 | The product copies an input buffer to an output buffer without verifying that the size of the input buffer is less than the size of the output buffer. |
Attack-Flow Graph
AI Powered Q&A
How does this vulnerability affect compliance with common standards and regulations (like GDPR, HIPAA)?:
The provided information does not specify how the CVE-2026-7101 vulnerability affects compliance with common standards and regulations such as GDPR or HIPAA.
Can you explain this vulnerability to me?
The CVE-2026-7101 vulnerability affects the Tenda F456 router, version 1.0.0.5. It is a stack-based buffer overflow found in the HTTP daemon (httpd) component, specifically within the function formWrlclientSet.
The vulnerability arises because the function reads a user-supplied parameter named "GO" and passes it to the ask_to_reboot function without performing any length validation. Inside ask_to_reboot, the parameter is used in a sprintf call that writes into a fixed-size stack buffer, leading to a potential overflow.
An attacker can exploit this by sending a specially crafted HTTP POST request to the /goform/WrlclientSet endpoint with an excessively long "GO" parameter. This unchecked buffer overflow can result in denial of service (DoS) or remote code execution (RCE) on the device.
How can this vulnerability impact me? :
Exploitation of this vulnerability can lead to denial of service (DoS), causing the affected device to crash or become unresponsive.
More critically, it can allow remote code execution (RCE), enabling an attacker to execute arbitrary code on the device remotely. This could lead to full compromise of the router, potentially allowing attackers to intercept, modify, or disrupt network traffic.
How can this vulnerability be detected on my network or system? Can you suggest some commands?
This vulnerability can be detected by monitoring for HTTP POST requests sent to the /goform/WrlclientSet endpoint containing an excessively long "GO" parameter. Such requests may indicate attempts to exploit the buffer overflow.
A practical detection method is to capture and inspect network traffic for suspicious POST requests with unusually large "GO" parameter values.
- Use a network packet capture tool like tcpdump or Wireshark to filter HTTP POST requests to /goform/WrlclientSet.
- 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/WrlclientSet'
- Alternatively, use curl or similar tools to test the endpoint by sending a POST request with a large "GO" 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 /goform/WrlclientSet endpoint to trusted networks only, such as by implementing firewall rules.
Avoid exposing the Tenda F456 router's HTTP management interface to untrusted networks or the internet.
Monitor for suspicious POST requests with large "GO" parameters and block or alert on such traffic.
If available, update the device firmware to a version that patches this vulnerability.