CVE-2026-10187: Totolink N300RH Web Management wireless.so setWiFiBasicConfig stack-based overflow

Synopsis

A stack-based buffer overflow exists in the web management interface of the Totolink N300RH router (firmware 6.1c.1353_B20190305). The vulnerability is reachable over the network without any authentication, triggered by supplying an oversized value to the KeyStr argument of the setWiFiBasicConfig function in wireless.so. Successful exploitation gives an attacker full read/write access to the device and the ability to crash or take control of it. No vendor patch has been published; HarborGuard tracks the advisory and will make a patched rebuild available as soon as an upstream fix is released.

HarborGuard Coverage

Exploit Conditions

• Network reachabilityRequired

  The vulnerable setWiFiBasicConfig handler is exposed over the network through the web management interface, meaning an attacker must be able to reach the device's HTTP/HTTPS management port.

• AuthenticationNot required

  The CVSS vector specifies PR:N, meaning no account or session credential is needed to send the malicious KeyStr argument and trigger the overflow.

• Victim interactionNot required

  The CVSS vector specifies UI:N, so exploitation is fully attacker-driven and does not require any action from a user or administrator on the target device.

• Attack complexityDetail

  AC:L indicates the exploit is reliable and condition-free, requiring no race conditions, memory-layout guessing, or special environmental setup.

Blast Radius

• Reads all data accessible to the compromised web management process, including stored Wi-Fi credentials, pre-shared keys, and administrative credentials.
• Modifies device configuration, enabling the attacker to change wireless settings, routing rules, or credentials to maintain persistence.
• Crashes the web management service or the broader device firmware, causing a denial-of-service for all users on the network segment served by the router.
• With code execution on the router, the attacker gains a foothold to pivot into the local network behind the device.