CVE-2025-20792 is a security vulnerability classified under CWE-617 (Reachable Assertion) affecting multiple MediaTek modem chipsets, including MT2735, MT6833 series, MT6853 series, MT6873 series, MT6880 series, MT6890 series, and MT8791T. The root cause is improper input validation within the modem firmware, which can trigger an assertion failure leading to a system crash. This vulnerability can be exploited remotely without requiring user interaction or elevated privileges by an attacker operating a rogue base station. When a user equipment (UE) connects to such a malicious base station, crafted inputs can cause the modem to crash, resulting in a denial of service condition. The affected modem versions include Modem NR15. The vulnerability was reserved in November 2024 and published in December 2025. Although no public exploits are currently known, the impact on device availability is significant, especially for mobile devices relying on these chipsets. The vulnerability affects the modem's ability to maintain stable network connectivity, potentially disrupting communications. MediaTek has identified a patch (MOLY01717526) to address this issue, though it is not linked in the provided data. This vulnerability is particularly concerning for mobile network operators, enterprises, and critical infrastructure relying on stable mobile communications. The lack of authentication or user interaction requirements lowers the barrier for exploitation, increasing risk. The vulnerability's scope covers a wide range of devices using these chipsets globally.

For European organizations, the primary impact of CVE-2025-20792 is the potential for remote denial of service on mobile devices and embedded systems using affected MediaTek modems. This can disrupt critical communications, especially for sectors relying on mobile connectivity such as emergency services, transportation, and industrial IoT deployments. Enterprises with mobile workforce devices or IoT devices using these chipsets may experience service interruptions, affecting business continuity. Telecom operators could face network stability issues if a significant number of devices are impacted by rogue base stations, potentially leading to customer dissatisfaction and reputational damage. The vulnerability could also be exploited in targeted attacks against high-value individuals or organizations by deploying rogue base stations in proximity. Given the widespread use of MediaTek chipsets in consumer and industrial devices, the disruption could be broad but localized to areas where rogue base stations can be deployed. The lack of need for user interaction or elevated privileges means attackers can exploit this vulnerability stealthily and remotely, increasing the risk of large-scale denial of service events.

1. Apply the official MediaTek patch (MOLY01717526) as soon as it becomes available and is integrated into device firmware updates. 2. Mobile device manufacturers and network operators should prioritize rolling out firmware updates to affected devices promptly. 3. Implement network monitoring solutions capable of detecting rogue base stations and anomalous signaling patterns to prevent devices from connecting to malicious infrastructure. 4. Employ mobile network security features such as mutual authentication and enhanced base station verification where supported to reduce the risk of rogue base station connections. 5. For enterprise and critical infrastructure deployments, consider using mobile device management (MDM) solutions to enforce timely updates and monitor device connectivity. 6. Educate users and administrators about the risks of connecting to untrusted networks and encourage the use of VPNs or secure communication channels when possible. 7. Collaborate with telecom providers to enhance detection and mitigation of rogue base stations within their networks. 8. Conduct regular security assessments of mobile and IoT devices to ensure firmware is up to date and vulnerabilities are addressed.