CVE-2025-11133 identifies a vulnerability in the 5G NR modem firmware of Unisoc (Shanghai) Technologies Co., Ltd.'s T8100, T9100, T8200, and T8300 chipsets. These chipsets are integrated into various Android devices running versions 13 through 16. The root cause is improper input validation (CWE-20) within the modem's processing of incoming data, which can be manipulated remotely by an attacker to trigger a system crash. This crash leads to a denial of service (DoS) condition, disrupting normal device operation. The vulnerability is exploitable over the network without requiring any privileges or user interaction, increasing the attack surface. The CVSS v3.1 score of 7.5 reflects a high severity due to the ease of exploitation and impact on availability, although confidentiality and integrity remain unaffected. No public exploits have been reported yet, but the potential for disruption in mobile communications is significant. The lack of available patches at the time of disclosure necessitates proactive monitoring and risk management. The vulnerability affects a broad range of Android versions, indicating a wide potential impact across devices using these chipsets. Given the critical role of modems in mobile connectivity, exploitation could degrade service quality or cause device reboots, impacting end users and enterprise operations reliant on mobile networks.

For European organizations, the primary impact is on availability and operational continuity. Devices using affected Unisoc chipsets may experience unexpected crashes or reboots, leading to service interruptions. This is particularly critical for sectors relying on mobile communications such as telecommunications providers, emergency services, logistics, and remote workforce operations. Disruptions could affect mobile network reliability, degrade user experience, and potentially interrupt critical communications. While the vulnerability does not expose data confidentiality or integrity, the denial of service could indirectly impact business processes and customer trust. Enterprises deploying IoT devices or mobile endpoints with these chipsets may face increased downtime or require costly device replacements or firmware updates. The absence of known exploits reduces immediate risk but does not eliminate the threat, especially as attackers may develop exploits post-disclosure. The impact is amplified in environments with high dependency on mobile connectivity and limited redundancy.

1. Coordinate with device manufacturers and Unisoc to obtain and apply firmware or software patches as soon as they become available. 2. Implement network-level monitoring to detect unusual traffic patterns targeting modem interfaces, which may indicate exploitation attempts. 3. Employ mobile device management (MDM) solutions to enforce timely updates and monitor device health status. 4. For critical infrastructure, consider deploying fallback communication channels or redundant devices to maintain availability during potential disruptions. 5. Educate IT and security teams about this vulnerability to ensure rapid incident response if symptoms of exploitation appear. 6. Restrict exposure of vulnerable devices to untrusted networks where possible, using network segmentation or VPNs. 7. Engage with telecom providers to understand their mitigation strategies and coordinate on threat intelligence sharing. 8. Maintain an inventory of devices using affected chipsets to prioritize patching and monitoring efforts.