The vulnerability resides in the firmware update component at /www/cgi/ssi on the TRENDnet TEW‑821DAP, allowing sensitive information to be sent in cleartext. Attackers can trigger this remotely, and the disclosed exploit is reported to be of high complexity and difficult to execute, yet publicly available. Because the flaw leaks confidential data, the primary impact is a breach of confidentiality.

The issue affects TRENDnet TEW‑821DAP firmware version 1.12B01. This model is an end‑of‑life product, unsupported for over eight years, and is no longer available from the manufacturer.

With a CVSS score of 6.3 the vulnerability falls into the medium severity range. The EPSS score is not available, but the public disclosure of the exploit increases the likelihood of an attack. The vulnerability is not listed in the CISA KEV catalog. Because the device is accessed via its firmware update interface, the likely attack vector is remote; however, operational constraints such as lack of vendor support mean that remediation relies on replacing or disabling the device rather than applying a patch.