CVE-2026-7609
Command Injection in TRENDnet TEW-821DAP Firmware
Publication date: 2026-05-02
Last updated on: 2026-05-06
Assigner: VulDB
Description
Description
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| trendnet | tew-821dap_firmware | 1.12b01 |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-77 | The product constructs all or part of a command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended command when it is sent to a downstream component. |
| CWE-78 | The product constructs all or part of an OS command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended OS command when it is sent to a downstream component. |
Attack-Flow Graph
AI Powered Q&A
How can this vulnerability be detected on my network or system? Can you suggest some commands?
This vulnerability can be detected by testing the diagnostic tool's handling of IP address inputs for command injection. Specifically, sending crafted AJAX POST requests to the tools_diagnostic function with IP parameters containing shell metacharacters such as ;, |, or $ can reveal if command injection is possible.
A practical detection method involves sending a traceroute diagnostic request with an IP address parameter that includes injected commands, for example: 127.0.0.1" -f /dev/null; <command>; #. If the system executes the injected command, the vulnerability is present.
Since the vulnerability is triggered via the AJAX POST request to the diagnostic function, monitoring network traffic for suspicious POST requests to the diagnostic endpoint with unusual characters in the IP address field can also help detect exploitation attempts.
What immediate steps should I take to mitigate this vulnerability?
Immediate mitigation steps include avoiding the use of the vulnerable firmware version (up to 1.12B01) on the TRENDnet TEW-821DAP device, as this product is already end-of-life and no longer supported by the vendor.
Since the vendor no longer provides updates or patches, the best mitigation is to discontinue use of the affected hardware or isolate it from untrusted networks to prevent remote exploitation.
Additionally, monitoring and filtering network traffic to block suspicious AJAX POST requests containing shell metacharacters targeting the diagnostic function can reduce the risk of 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 this vulnerability on compliance with common standards and regulations such as GDPR or HIPAA.
Can you explain this vulnerability to me?
This vulnerability is a command injection flaw found in the firmware update process of the TRENDnet TEW-821DAP router, specifically in the tools_diagnostic function of the ssi program. It occurs because the IP address input used for network diagnostics is not properly sanitized for shell metacharacters such as ;, |, and $. This allows an attacker to inject and execute arbitrary operating system commands remotely by sending a specially crafted AJAX POST request.
How can this vulnerability impact me? :
This vulnerability can allow a remote attacker to execute arbitrary commands on the affected device without user interaction. This could lead to unauthorized control over the router, enabling actions such as executing malicious code or causing denial of service conditions. Since the device is no longer supported, it is unlikely to receive patches, increasing the risk if the device is still in use.