NetworkActiv Web Server 4.0 has a buffer overflow in the username field of its security options. A local attacker can supply an excessively long string to the Set username interface, causing the application to crash and resulting in a denial of service. The flaw is a classic buffer overflow (CWE‑787) that affects only the availability of the web server.

NetworkActiv Web Server version 4.0 is the only product version listed as impacted in the Advisory. No other products or versions are mentioned as affected.

The CVSS score of 6.9 reflects moderate severity with local access required. The EPSS score of less than 1 % suggests a low likelihood of exploitation. This vulnerability is not in CISA's KEV catalog. The attack vector is local interaction with the Set username interface, which must be accessed by the attacker to trigger the overflow and cause a denial of service.