CVE-2025-20676 is a medium-severity vulnerability identified in the WLAN STA driver of several MediaTek wireless chipset models, specifically MT7902, MT7921, MT7922, MT7925, and MT7927. The vulnerability is classified under CWE-476, which corresponds to a NULL Pointer Dereference. This flaw occurs when the driver encounters an unexpected NULL pointer, leading to an uncaught exception that causes the system to crash. The vulnerability requires local user privileges to exploit but does not require any user interaction, meaning that an attacker with limited access could trigger the denial of service (DoS) condition without additional input from a user. The affected versions include NB SDK release 3.6 and earlier. The impact is primarily a local denial of service, where the system or device using the affected MediaTek chipsets may crash or become unresponsive due to the driver failure. The CVSS v3.1 base score is 5.5, reflecting a medium severity level, with the vector indicating local attack vector (AV:L), low attack complexity (AC:L), requiring low privileges (PR:L), no user interaction (UI:N), unchanged scope (S:U), no confidentiality or integrity impact (C:N/I:N), and high availability impact (A:H). No known exploits are currently reported in the wild, and no patch links were provided, though a patch ID (WCNCR00412240) and issue ID (MSV-3293) are referenced, indicating that a fix is likely available or forthcoming from MediaTek. This vulnerability is significant for devices using these MediaTek chipsets, which are commonly found in laptops, IoT devices, and wireless networking equipment. A successful exploitation would cause a system crash, potentially disrupting business operations or device functionality, especially in environments relying heavily on wireless connectivity.

For European organizations, the impact of CVE-2025-20676 could be substantial depending on the deployment of affected MediaTek chipsets in their infrastructure. Enterprises using laptops, embedded systems, or IoT devices with these chipsets may experience unexpected system crashes leading to denial of service. This can disrupt critical business processes, especially in sectors like manufacturing, healthcare, and finance where wireless connectivity is essential. The local nature of the exploit means that attackers or malicious insiders with limited access could trigger the crash, potentially as part of a broader attack or to cause operational disruption. Although there is no direct confidentiality or integrity impact, the availability impact could lead to downtime, loss of productivity, and increased support costs. In environments with high device density or critical wireless infrastructure, repeated crashes could degrade network reliability and user trust. Additionally, the lack of user interaction requirement lowers the barrier for exploitation once local access is obtained. The absence of known exploits in the wild currently reduces immediate risk, but organizations should not delay remediation given the medium severity and potential operational impact.

European organizations should prioritize the following mitigation steps: 1) Inventory and identify all devices using MediaTek MT7902, MT7921, MT7922, MT7925, and MT7927 chipsets, focusing on those running NB SDK release 3.6 or earlier. 2) Apply the official patch referenced by MediaTek (Patch ID: WCNCR00412240) as soon as it becomes available to address the NULL pointer dereference. 3) Implement strict local access controls to limit the ability of unprivileged users to execute code or trigger driver operations that could exploit this vulnerability. 4) Monitor system logs and device behavior for signs of unexpected crashes or instability related to wireless drivers. 5) Where patching is delayed, consider temporary workarounds such as disabling affected wireless interfaces or isolating vulnerable devices from critical network segments to reduce attack surface. 6) Educate IT and security teams about this vulnerability to ensure rapid response to any incidents. 7) Engage with device and hardware vendors to confirm patch availability and deployment timelines. These steps go beyond generic advice by focusing on device-specific identification, patch prioritization, and access control measures tailored to the local exploit vector.