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 with network proximity, such as on the same Wi-Fi or local network—to potentially derive or guess the secretKey. With this key, the attacker can access backup data from applications transferred or stored via Smart Switch. The vulnerability does not require any privileges or user interaction, increasing the risk of exploitation. The CVSS v3.1 score of 8.8 indicates a high severity, with attack vector being adjacent network (AV:A), low attack complexity (AC:L), no privileges required (PR:N), and no user interaction (UI:N). The impact covers confidentiality, integrity, and availability (C:H/I:H/A:H), meaning attackers can read, modify, or disrupt backup data. Although no exploits have been observed in the wild, the vulnerability poses a significant risk to data security, especially for organizations relying on Smart Switch for device backups. The lack of patch links suggests that users should upgrade to version 3.7.68.6 or later where the issue is resolved. The vulnerability highlights the importance of strong cryptographic randomness in securing backup keys to prevent unauthorized data access.

For European organizations, the impact of CVE-2025-21078 is substantial. Many enterprises and government agencies use Samsung devices and Smart Switch for data backup and migration. Exploitation could lead to unauthorized disclosure of sensitive application data, including personal, financial, or intellectual property information. This breach of confidentiality could result in regulatory non-compliance under GDPR, leading to fines and reputational damage. Integrity and availability impacts mean attackers could tamper with backup data or disrupt backup processes, potentially causing data loss or corruption. Sectors such as finance, healthcare, and critical infrastructure are particularly vulnerable due to the sensitivity of their data and reliance on mobile device backups. The adjacent network attack vector implies that attackers need local network access, which could be achieved through compromised Wi-Fi networks or insider threats. This elevates the risk in environments with weak network segmentation or insufficient wireless security controls. Overall, the vulnerability threatens data security and operational continuity for European organizations using affected Samsung Smart Switch versions.

1. Immediate upgrade to Samsung Smart Switch version 3.7.68.6 or later, where the vulnerability is patched. 2. Implement strict network segmentation to isolate devices running Smart Switch from untrusted or public networks, minimizing adjacent attacker access. 3. Enforce strong Wi-Fi security protocols (WPA3 or at least WPA2 with strong passwords) to reduce the risk of local network compromise. 4. Monitor network traffic for unusual access patterns to backup services, especially on local networks. 5. Educate users about the risks of connecting devices to untrusted networks when performing backups or data transfers. 6. Employ endpoint security solutions that can detect anomalous behavior related to backup data access. 7. Regularly audit backup data integrity and access logs to detect potential unauthorized access or tampering. 8. Consider alternative secure backup solutions with robust cryptographic protections if Smart Switch cannot be updated promptly. These measures collectively reduce the attack surface and mitigate the risk of exploitation.