CVE-2026-5156
Remote Stack-Based Buffer Overflow in Tenda CH22 Parameter Handler
Publication date: 2026-03-31
Last updated on: 2026-04-02
Assigner: VulDB
Description
Description
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| tenda | ch22_firmware | 1.0.0.1 |
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-787 | The product writes data past the end, or before the beginning, of the intended buffer. |
| 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?
CVE-2026-5156 is a stack-based buffer overflow vulnerability found in the Tenda CH22 device, version 1.0.0.1. It occurs in the HTTP daemon's formQuickIndex function, which processes user-supplied parameters such as "mit_linktype" and "PPPOEPassword." When the parameter "mit_linktype" is set to 2, the function passes a variable to another function without validating its length, causing a buffer overflow on the stack.
An attacker can exploit this vulnerability remotely by sending a specially crafted HTTP POST request to the /goform/QuickIndex endpoint with an excessively long "PPPOEPassword" parameter. This can lead to denial of service (DoS) or potentially allow the attacker to execute arbitrary code on the device.
How can this vulnerability impact me? :
This vulnerability can impact you by allowing a remote attacker to cause a denial of service (DoS) on the affected Tenda CH22 device, making it unavailable or unstable.
More severely, the attacker may be able to execute arbitrary code remotely, which could lead to full compromise of the device, unauthorized access, data theft, or further attacks within your 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/QuickIndex endpoint, especially those containing the parameter mit_linktype=2 along with an unusually long PPPOEPassword parameter.
A practical detection method is to capture and analyze network traffic for such crafted requests that may trigger the stack-based buffer overflow.
- Use a network packet capture tool like tcpdump or Wireshark to filter HTTP POST requests to /goform/QuickIndex.
- 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/QuickIndex'
- Use tools like curl or custom scripts to test the endpoint by sending POST requests with mit_linktype=2 and varying lengths of PPPOEPassword to observe abnormal behavior.
What immediate steps should I take to mitigate this vulnerability?
Immediate mitigation steps include restricting access to the vulnerable /goform/QuickIndex endpoint to trusted networks or IP addresses to prevent remote exploitation.
Additionally, monitoring and blocking suspicious HTTP POST requests with mit_linktype=2 and unusually long PPPOEPassword parameters can help reduce risk.
If possible, update the firmware of the Tenda CH22 device to a version that patches this vulnerability.
As a temporary measure, disabling or restricting the HTTP daemon (httpd) service or applying firewall rules to block access to the /goform/QuickIndex endpoint can help mitigate exploitation.
How does this vulnerability affect compliance with common standards and regulations (like GDPR, HIPAA)?:
The provided information does not specify any direct impact of the CVE-2026-5156 vulnerability on compliance with common standards and regulations such as GDPR or HIPAA.