An improper input sanitization flaw in the httpd component of the TP‑Link TD‑W8961N router allows an attacker to send specially formatted requests that trigger a processing error, causing the httpd service to crash and resulting in a loss of web‑based management functionality. The weakness is an example of improper validation of user supplied data, which can lead to a temporary interruption of services.

The vulnerability applies exclusively to the TP‑Link TD‑W8961N router running firmware version 4.0. No other TP‑Link products or firmware revisions are identified as affected in the available data.

The CVSS score of 7.1 places this vulnerability in the moderate‑to‑high impact category. An EPSS score of less than 1% indicates a low likelihood of current exploitation, and it is not listed in the CISA KEV catalog. Based on the description, the attack vector is inferred to originate from a remote entity capable of sending HTTP requests to the device; authentication is not required to trigger the crash.