CVE-2025-21078 is a vulnerability identified in Samsung Mobile's Smart Switch application, specifically in versions prior to 3.7.68.6. The root cause is the use of insufficiently random values for the secretKey used in the backup process, classified under CWE-330 (Use of Insufficiently Random Values). This cryptographic weakness allows an adjacent attacker—someone positioned within the same local network or with network proximity—to potentially derive or guess the secretKey. With this key, the attacker can access backup data from applications stored or transferred via Smart Switch, leading to unauthorized disclosure of sensitive information. The vulnerability does not require any privileges or user interaction, making it easier to exploit in environments where the attacker can gain network adjacency. The CVSS v3.1 score of 8.8 reflects high impact on confidentiality, integrity, and availability, with low attack complexity and no required privileges or user interaction. Although no exploits are currently known in the wild, the vulnerability poses a significant risk to users relying on Smart Switch for device backups. The lack of patch links suggests that users should verify updates directly from Samsung. The vulnerability affects the confidentiality of backup data, potentially allowing attackers to extract personal or corporate information, modify backups, or disrupt backup availability. This is particularly concerning for enterprise environments where mobile device backups may contain critical business data. The vulnerability's exploitation scope is limited to adjacent network attackers, emphasizing the importance of local network security controls.

For European organizations, the impact of CVE-2025-21078 can be substantial. Many enterprises and individuals use Samsung Smart Switch to backup and transfer mobile data, including sensitive corporate information, credentials, and personal data. An attacker exploiting this vulnerability could gain unauthorized access to backup data, leading to data breaches, intellectual property theft, and potential compliance violations under GDPR due to exposure of personal data. The integrity of backups could also be compromised, allowing attackers to inject malicious data or disrupt recovery processes, impacting business continuity. Availability could be affected if backups are corrupted or access is denied. The vulnerability's exploitation requires network adjacency, which means attackers could leverage compromised Wi-Fi networks, internal networks, or malicious insiders. This risk is heightened in environments with lax network segmentation or unsecured wireless access points. Given the high CVSS score and the critical nature of backup data, European organizations must prioritize remediation to avoid significant operational and reputational damage.

1. Immediate upgrade to Samsung Smart Switch version 3.7.68.6 or later, where the vulnerability is addressed. 2. Restrict access to local networks where Smart Switch is used, employing strong Wi-Fi encryption (WPA3 preferred) and network segmentation to isolate backup devices from untrusted users. 3. Implement network monitoring to detect unusual access patterns or attempts to access backup data. 4. Educate users about the risks of connecting to untrusted networks when performing backups. 5. Use endpoint security solutions to detect and block suspicious activities related to Smart Switch. 6. Where possible, enforce multi-factor authentication and encryption for backup data beyond the application’s default mechanisms. 7. Regularly audit backup data access logs to identify unauthorized attempts. 8. Coordinate with Samsung support channels to obtain official patches and security advisories. 9. Consider alternative secure backup solutions if immediate patching is not feasible.