CVE-2025-20743 is a use-after-free vulnerability identified in the clkdbg (clock debug) component of multiple MediaTek System on Chips (SoCs), including but not limited to MT2718, MT6761, MT6765, MT6768, MT6781, MT6853, and many others spanning a broad range of MediaTek’s product line. The vulnerability exists due to improper handling of memory, where a resource is freed but later accessed, leading to undefined behavior. This can be exploited by a local attacker who already has System-level privileges on an affected device to escalate their privileges further, potentially gaining higher control over the system. The flaw does not require user interaction, which increases the risk if an attacker has initial access. The vulnerability affects devices running Android versions 14.0, 15.0, and 16.0 that incorporate these MediaTek chipsets. The CVSS 3.1 base score is 4.2, reflecting a medium severity primarily because exploitation requires high privileges (System) and local access, limiting the attack surface. The impact includes limited confidentiality, integrity, and availability consequences, as the attacker must already have significant control. No public exploits or widespread attacks have been reported to date. The vendor has acknowledged the issue with Patch ID ALPS10136671 and Issue ID MSV-4651, though no direct patch links are provided. This vulnerability is categorized under CWE-416 (Use After Free), a common memory corruption issue that can lead to privilege escalation or code execution if exploited effectively.

For European organizations, the primary impact of CVE-2025-20743 lies in environments where MediaTek-based Android devices are used, particularly in enterprise mobile deployments or IoT ecosystems. Since exploitation requires existing System privileges, the vulnerability mainly threatens scenarios where an attacker has already compromised a device or insider threats exist. Successful exploitation could allow attackers to bypass security controls, escalate privileges, and potentially manipulate sensitive data or system configurations. This could lead to data breaches, unauthorized access to corporate resources, or disruption of services relying on affected devices. Given the widespread use of MediaTek chipsets in consumer and industrial devices, organizations using such hardware in their infrastructure or employee devices may face increased risk. The lack of user interaction requirement means automated or scripted attacks could be feasible once initial access is obtained. However, the medium severity score and prerequisite privileges limit the overall risk compared to remote or unauthenticated vulnerabilities.

1. Apply vendor patches promptly once they become available to address this use-after-free vulnerability. Monitor MediaTek and Android security bulletins for updates related to Patch ID ALPS10136671. 2. Restrict System-level privileges on devices to trusted applications and users only, minimizing the risk of privilege escalation from compromised accounts or apps. 3. Employ mobile device management (MDM) solutions to enforce security policies, control app installations, and monitor device integrity. 4. Conduct regular security audits and vulnerability assessments on devices running affected MediaTek chipsets, especially those used in sensitive environments. 5. Implement network segmentation and least privilege principles to limit lateral movement if a device is compromised. 6. Educate users and administrators about the risks of privilege escalation vulnerabilities and the importance of applying updates. 7. Consider deploying runtime protections such as memory corruption mitigations (e.g., ASLR, DEP) where supported by the device firmware and OS. 8. Monitor for unusual system behavior or privilege escalations that could indicate exploitation attempts. 9. For critical deployments, evaluate alternative hardware platforms with a stronger security posture if timely patching is not feasible.