CVE-2025-21476 is a classic buffer overflow vulnerability (CWE-120) identified in Qualcomm Snapdragon chipsets, specifically affecting a wide range of models including QCM5430, SM8550, and WCN series among others. The flaw occurs during the handshake process with the Trusted Virtual Machine (TVM), where parameters are passed without proper size validation, leading to memory corruption. This vulnerability can be exploited by an attacker with limited privileges on the device (local access required) but does not require user interaction. Successful exploitation can result in arbitrary code execution within the trusted execution environment, potentially allowing privilege escalation, unauthorized access to sensitive data, and disruption of device operations. The vulnerability has a CVSS v3.1 base score of 7.8, reflecting high impact on confidentiality, integrity, and availability, with low attack complexity and limited privileges required. Although no public exploits are reported yet, the broad range of affected Snapdragon chipsets means many mobile devices and embedded systems could be vulnerable. The Trusted Virtual Machine is a critical component for secure operations on Snapdragon platforms, so compromising it undermines the device’s security foundation. The vulnerability was reserved in December 2024 and published in September 2025, indicating recent discovery and disclosure. No patches are currently linked, so affected organizations must monitor Qualcomm advisories closely. This vulnerability is particularly concerning for environments relying heavily on Snapdragon-powered devices for secure communications and operations.

For European organizations, the impact of CVE-2025-21476 could be significant due to the widespread use of Qualcomm Snapdragon chipsets in smartphones, tablets, and IoT devices. Exploitation could lead to unauthorized access to sensitive corporate data, compromise of secure communications, and potential disruption of critical services relying on affected devices. The ability to execute arbitrary code within the Trusted Virtual Machine could allow attackers to bypass security controls, install persistent malware, or exfiltrate confidential information. This is especially critical for sectors such as finance, government, telecommunications, and critical infrastructure where device security is paramount. Additionally, compromised devices could be used as footholds for lateral movement within corporate networks. The local access requirement somewhat limits remote exploitation but insider threats or malware already present on devices could leverage this vulnerability. The absence of known exploits currently provides a window for proactive mitigation, but the high severity score underscores the urgency of addressing this issue to prevent future attacks.

1. Monitor Qualcomm’s official security advisories and promptly apply any released patches or firmware updates addressing CVE-2025-21476. 2. Implement strict access controls to limit local access to devices, including enforcing strong authentication and physical security measures. 3. Employ endpoint detection and response (EDR) solutions capable of detecting anomalous behavior indicative of exploitation attempts targeting the Trusted Virtual Machine. 4. Conduct regular security audits and vulnerability assessments on devices using affected Snapdragon chipsets to identify potential compromise. 5. For organizations deploying IoT or embedded systems with these chipsets, segment networks to reduce the risk of lateral movement if a device is compromised. 6. Educate users and administrators about the risks of local privilege escalation vulnerabilities and the importance of device hygiene. 7. Where possible, disable or restrict unnecessary services that interact with the Trusted Virtual Machine to reduce the attack surface. 8. Collaborate with device vendors and suppliers to ensure timely updates and security support for affected hardware. 9. Maintain an inventory of devices using affected Snapdragon models to prioritize patching and monitoring efforts. 10. Consider deploying mobile threat defense solutions that can detect exploitation attempts on mobile endpoints.