CVE-2025-20721 is a vulnerability classified as CWE-787 (Out-of-bounds Write) found in the imgsensor component of MediaTek chipsets including MT6886, MT6897, MT6899, MT6985, MT6989, MT6991, MT8195, MT8196, MT8370, MT8390, MT8395, MT8792, and MT8793. These chipsets are embedded in various Android devices running versions 13.0 through 16.0 and IoT devices using IOT-v25.0. The vulnerability stems from a missing bounds check during memory operations, which can lead to an out-of-bounds write condition. This flaw can be exploited by an attacker who already possesses System-level privileges on the device, enabling local privilege escalation without requiring any user interaction. The escalation could allow the attacker to gain higher privileges, potentially leading to full device compromise or the ability to manipulate sensitive data and system functions. While no public exploits have been reported, the vulnerability's presence in widely deployed chipsets makes it a significant concern. The lack of a CVSS score necessitates an independent severity assessment. The vulnerability's exploitation complexity is moderate since it requires prior system-level access, but the impact on confidentiality, integrity, and availability can be substantial. The vendor has acknowledged the issue and assigned Patch ID ALPS10089545, but no direct patch links are currently available.

For European organizations, the impact of CVE-2025-20721 could be considerable, especially for those relying on mobile devices or IoT infrastructure powered by affected MediaTek chipsets. Successful exploitation could lead to privilege escalation, enabling attackers to bypass security controls, access sensitive corporate data, or disrupt device functionality. This is particularly critical for sectors such as finance, healthcare, telecommunications, and government, where device integrity and data confidentiality are paramount. The vulnerability's local nature means attackers must first gain system-level access, which might be achieved through other vulnerabilities or insider threats, making it a potential component of multi-stage attacks. The widespread use of MediaTek chipsets in consumer and enterprise devices across Europe increases the attack surface. Additionally, compromised devices could be leveraged as entry points into corporate networks or for lateral movement, amplifying the risk. The absence of user interaction for exploitation facilitates stealthy attacks once initial access is obtained. Overall, the vulnerability could undermine trust in mobile and IoT device security, impacting operational continuity and regulatory compliance.

1. Apply vendor-provided patches immediately once available to remediate the out-of-bounds write vulnerability. 2. Implement strict access controls and monitoring to prevent unauthorized acquisition of System-level privileges, as exploitation requires such access. 3. Employ endpoint detection and response (EDR) solutions capable of identifying anomalous privilege escalation attempts on devices with affected chipsets. 4. Conduct regular security audits and penetration testing focusing on privilege escalation vectors within mobile and IoT environments. 5. Limit installation of untrusted applications and enforce application whitelisting to reduce the risk of initial compromise. 6. Maintain up-to-date device firmware and operating system versions to benefit from security improvements. 7. Educate users and administrators about the risks of privilege escalation and the importance of device security hygiene. 8. For organizations deploying IoT devices, segment these devices on separate networks to contain potential breaches. 9. Monitor vendor advisories and threat intelligence feeds for updates or emerging exploits related to this vulnerability.