CVE-2025-31718 is a vulnerability identified in the modem firmware of multiple Unisoc (Shanghai) Technologies Co., Ltd. chipsets, specifically models T606, T612, T616, T750, T765, T760, T770, T820, S8000, T8300, and T9300. These chipsets are integrated into a range of mobile devices running Android versions 13 through 16. The root cause is improper input validation within the modem component, classified under CWE-20, which leads to a possible system crash. This crash can be triggered remotely without requiring any authentication or user interaction, indicating a network attack vector with low complexity. The consequence of exploitation is primarily a denial of service (availability impact) due to system crashes, but the vulnerability also enables remote escalation of privileges, potentially allowing attackers to gain control over the device's modem functions. The CVSS v3.1 score is 7.5, reflecting high severity with network attack vector (AV:N), low attack complexity (AC:L), no privileges required (PR:N), 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 patches or known exploits are currently reported, but the vulnerability's presence in widely used chipsets makes it a significant threat. The modem's critical role in device communication means exploitation could disrupt mobile connectivity and compromise device stability. The vulnerability was reserved in April 2025 and published in October 2025, indicating recent discovery and disclosure.

For European organizations, the impact of CVE-2025-31718 can be substantial. Many enterprises and public sector entities rely on mobile devices for communication, remote work, and operational continuity. Devices using affected Unisoc chipsets could experience unexpected crashes, leading to loss of connectivity and productivity. The remote escalation of privilege could allow attackers to manipulate modem functions, potentially intercepting or disrupting communications, which is critical for sectors such as finance, healthcare, and government. The availability impact could extend to IoT devices and embedded systems using these chipsets, affecting industrial control systems or critical infrastructure. Additionally, the lack of required authentication or user interaction lowers the barrier for attackers, increasing the risk of widespread exploitation. Although no active exploits are known, the potential for disruption and unauthorized control poses a threat to data integrity and operational resilience in European organizations.

Mitigation should focus on a multi-layered approach: 1) Device manufacturers and vendors must prioritize releasing firmware and Android OS updates that address this vulnerability; organizations should ensure timely deployment of these patches. 2) Network administrators should implement monitoring and anomaly detection for unusual modem or cellular traffic patterns that could indicate exploitation attempts. 3) Organizations should maintain an inventory of devices using Unisoc chipsets and assess exposure. 4) Employ network segmentation and restrict device access to sensitive networks to limit potential impact. 5) Use mobile device management (MDM) solutions to enforce security policies and update compliance. 6) Collaborate with mobile carriers to monitor and mitigate suspicious activities at the network level. 7) Educate users about the importance of applying updates promptly and reporting device instability. These steps go beyond generic advice by emphasizing vendor coordination, network-level defenses, and asset management specific to the affected chipsets.