CVE-2025-20680 is a critical heap overflow vulnerability identified in the Bluetooth drivers of several MediaTek wireless chipset models, specifically MT7902, MT7920, MT7921, MT7922, MT7925, and MT7927. The root cause is an incorrect bounds check within the Bluetooth driver code, leading to an out-of-bounds write on the heap memory. This type of vulnerability falls under CWE-122 (Heap-based Buffer Overflow), which can allow attackers to corrupt memory, potentially leading to arbitrary code execution or privilege escalation. Notably, exploitation requires no user interaction and no prior privileges, meaning an attacker can trigger the vulnerability remotely or locally without authentication. The vulnerability affects devices running NB SDK release 3.6 and earlier versions. The CVSS v3.1 score is 9.8, indicating a critical severity level with network attack vector, low attack complexity, no privileges required, no user interaction, and high impact on confidentiality, integrity, and availability. Although no known exploits are currently reported in the wild, the vulnerability's characteristics make it a prime target for attackers aiming to gain elevated privileges on affected devices. MediaTek chipsets are widely used in various consumer electronics, including laptops, IoT devices, and mobile computing platforms, making this vulnerability significant in scope. The lack of a publicly available patch link suggests that affected organizations should prioritize obtaining and applying vendor updates or mitigations as soon as they become available to prevent exploitation.

For European organizations, the impact of CVE-2025-20680 can be substantial. MediaTek chipsets are commonly integrated into a broad range of wireless communication devices, including laptops, IoT devices, and embedded systems used in enterprise and industrial environments. Successful exploitation could allow attackers to escalate privileges locally, potentially gaining control over affected devices. This could lead to unauthorized access to sensitive data, disruption of critical services, or lateral movement within corporate networks. Given the Bluetooth driver context, devices relying on wireless connectivity for operational functions are at risk, including those in sectors such as manufacturing, healthcare, and smart infrastructure. The critical severity and ease of exploitation without user interaction increase the urgency for European organizations to assess their device inventories for affected hardware and implement mitigations promptly. Additionally, the potential for this vulnerability to be leveraged in targeted attacks or supply chain compromises could impact organizations with high-value intellectual property or critical infrastructure in Europe.

1. Immediate inventory and identification of devices using MediaTek MT7902, MT7920, MT7921, MT7922, MT7925, and MT7927 chipsets, especially those running NB SDK release 3.6 or earlier. 2. Engage with MediaTek and device vendors to obtain and apply the official security patches or firmware updates addressing CVE-2025-20680 as soon as they are released. 3. Until patches are available, consider disabling Bluetooth functionality on critical devices where feasible to reduce the attack surface. 4. Implement network segmentation to isolate devices with vulnerable chipsets from sensitive network segments. 5. Monitor system logs and network traffic for unusual Bluetooth activity or attempts to exploit heap overflow conditions. 6. Employ endpoint detection and response (EDR) solutions capable of detecting anomalous behaviors indicative of exploitation attempts. 7. Educate IT and security teams about the vulnerability specifics to ensure rapid response to any emerging exploit reports. 8. Coordinate with supply chain partners to ensure that devices procured or deployed are free from this vulnerability or have been patched.