CVE-2026-36809

Vulnerability

A buffer overflow vulnerability exists in the formModifyWebAuthWhiteUser function of Shenzhen Tenda Technology Co., Ltd Tenda W15E v15.11.0.10. The vulnerability is triggered when the webAuthWhiteID parameter, influenced by a user, is used in printf and sprintf commands without proper bounds checking, leading to a buffer overflow. The vulnerable code path is reachable if the parameters webAuthWhiteUserType, webAuthWhiteUser, and webAuthUserPwd are not null, and webAuthWhiteUserType is set to mac [1].

Exploitation

An attacker can exploit this vulnerability by sending a crafted HTTP request to the formModifyWebAuthWhiteUser CGI endpoint. The request must include parameters such as webAuthWhiteUserType set to mac, webAuthWhiteUser and webAuthUserPwd set to any value, and a long webAuthWhiteID parameter, for example, 888*a (where 'a' represents a string of characters). This crafted request triggers the buffer overflow condition [1].

Impact

Successful exploitation of this vulnerability results in a Denial of Service (DoS). This can manifest as a crash of the affected process or instability of the device, rendering it inoperable for legitimate users [1].

Mitigation

As of the available references, a patched version for Tenda W15E v15.11.0.10 has not been disclosed. No workarounds are provided. The device is not listed as end-of-life or part of the Known Exploited Vulnerabilities (KEV) catalog. Users are advised to check for future updates from the vendor. [1]