CVE-2026-36803

Vulnerability

A buffer overflow vulnerability exists in the qossetting function of Shenzhen Tenda Technology Co., Ltd Tenda PW201A v1.0.5, specifically within the handling of the page parameter. This function, identified by address 0x42e1c4 and registered via websFormDefine("qossetting",0x42e1c4), retrieves user-influenced HTTP parameters using websGetVar. The page parameter is then used in a sprintf command, leading to a buffer overflow when its value is excessively long [1].

Exploitation

An attacker can exploit this vulnerability by sending a crafted HTTP request to the qossetting CGI endpoint. The request must include a page parameter with a value significantly longer than expected, for example, a string of 888 or more characters. This requires the attacker to have network access to the device [1].

Impact

Successful exploitation of this buffer overflow vulnerability can lead to a Denial of Service (DoS) condition. This may manifest as a process crash or device instability, rendering the device inoperable for legitimate users [1].

Mitigation

No patched version or specific mitigation details are available in the provided references. The vulnerability affects Tenda PW201A v1.0.5, which is noted as the latest version in one reference [1].