Overview
CVE-2025-20757 describes a remote denial of service vulnerability affecting MediaTek modems. The vulnerability stems from improper input validation within the modem’s software. An attacker leveraging a rogue base station can exploit this weakness to trigger a system crash, leading to a denial of service condition on the affected device.
This vulnerability requires no user interaction and can be exploited remotely without requiring any additional execution privileges. The patch ID for this issue is MOLY01673751, and the internal issue ID is MSV-4644.
Published: 2025-12-02T03:16:17.050
Technical Details
The root cause of CVE-2025-20757 lies in insufficient input validation within the modem’s processing of signals received from cellular base stations. Specifically, when a User Equipment (UE, such as a mobile phone) connects to a rogue base station controlled by an attacker, the attacker can send specially crafted signals that contain malformed or unexpected data. The modem, without proper validation, attempts to process this data, leading to a system crash and subsequent denial of service. The precise location of the vulnerability within the modem firmware is related to the handling of certain control plane messages, which are susceptible to malformed parameters that can overflow buffers or trigger exceptions.
CVSS Analysis
Currently, the CVSS score for CVE-2025-20757 is listed as N/A (Not Available). However, based on the description of the vulnerability, which allows for remote denial of service without user interaction or special privileges, it is highly likely that once a CVSS score is assigned, it will be rated as HIGH or CRITICAL.
Key factors contributing to this assessment include:
- Remote Exploitability: The vulnerability can be exploited remotely.
- No User Interaction: No user action is required to trigger the vulnerability.
- No Privileges Required: The attacker does not need any special privileges.
- Denial of Service: The vulnerability results in a system crash, causing a denial of service.
Possible Impact
The exploitation of CVE-2025-20757 can have significant consequences:
- Service Disruption: Affected devices will experience a denial of service, rendering them unable to connect to cellular networks or perform essential communication functions.
- Device Unreliability: Repeated exploitation can lead to device instability and potentially permanent damage.
- Network Disruptions: In scenarios involving a large number of affected devices, a coordinated attack could potentially disrupt entire cellular networks.
Mitigation and Patch Steps
The primary mitigation for CVE-2025-20757 is to apply the official patch provided by MediaTek. Contact your device manufacturer to inquire about the availability of firmware updates containing patch ID MOLY01673751.
General security best practices can also help reduce the risk, although they may not completely prevent exploitation:
- Keep your device’s firmware updated with the latest security patches.
- Be cautious when connecting to unknown or untrusted Wi-Fi networks. Although this vulnerability is triggered via cellular networks, maintaining good security hygiene is always beneficial.
