CVE-2025-20760 is a vulnerability identified in multiple MediaTek modem chipsets (including MT2735 through MT8893 series) that arises from a reachable assertion triggered by reading uninitialized heap data caused by an uncaught exception within the modem firmware. This flaw exists in modem versions NR15, NR16, and NR17. The vulnerability can be exploited remotely without requiring any user interaction or elevated privileges by an attacker who controls a rogue base station to which a user equipment (UE) connects. Upon exploitation, the modem may experience a denial of service (DoS) condition, causing loss of modem functionality and potentially disrupting cellular connectivity. The root cause is a failure to properly initialize heap memory before use, leading to an assertion failure that crashes or halts modem operations. The vulnerability is classified under CWE-617 (Reachable Assertion), indicating that the assertion can be triggered by external input under attacker control. The CVSS v3.1 score of 6.5 (AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H) indicates that the attack vector is adjacent network (the cellular network), requires low attack complexity, no privileges or user interaction, and impacts availability only. While no known exploits are currently reported in the wild, the broad range of affected chipsets and the critical role of modems in mobile communications make this a significant concern. The patch identifier MOLY01676750 and issue ID MSV-4653 suggest that MediaTek has developed a fix, though deployment depends on device manufacturers and carriers. This vulnerability could be leveraged by attackers to disrupt mobile communications by forcing devices offline or causing repeated modem crashes, which is particularly critical for users relying on cellular connectivity for business, emergency services, or IoT operations.

For European organizations, the primary impact of CVE-2025-20760 is the potential disruption of cellular connectivity due to modem denial of service. This can affect enterprises relying on mobile broadband for remote work, IoT device management, or critical communications infrastructure. Telecommunications providers may face increased support costs and customer dissatisfaction if devices become unstable or lose connectivity. Industrial sectors using cellular modems for automation, logistics, or smart city applications could experience operational interruptions. The vulnerability could also be exploited in targeted attacks against high-value individuals or organizations by deploying rogue base stations in proximity, causing selective denial of service. Although confidentiality and integrity are not impacted, availability degradation can have cascading effects on business continuity and emergency response capabilities. The lack of required user interaction or privileges lowers the barrier for attackers, increasing the risk of widespread impact if rogue base stations are deployed in populated areas. Given the widespread use of MediaTek chipsets in consumer and enterprise mobile devices across Europe, the threat is relevant to a broad range of sectors including finance, healthcare, transportation, and government services.

Mitigation of CVE-2025-20760 requires a multi-layered approach. First, device manufacturers and mobile network operators must prioritize deployment of firmware updates incorporating the patch MOLY01676750 to affected MediaTek modems. Organizations should maintain an inventory of devices using these chipsets and coordinate with vendors to ensure timely updates. Network operators should enhance detection and prevention mechanisms for rogue base stations, including monitoring for anomalous base station behavior and employing secure base station authentication protocols where possible. Enterprises should implement mobile device management (MDM) solutions to enforce firmware updates and monitor device health. For critical infrastructure, consider fallback communication methods or redundant connectivity options to mitigate potential DoS impacts. Security teams should educate users about the risks of connecting to untrusted cellular networks, although user interaction is not required for exploitation. Finally, collaboration with telecom providers to share threat intelligence and incident response plans will improve resilience against exploitation attempts.