CVE-2023-7005 is a vulnerability classified under CWE-757, involving the selection of a less-secure algorithm during the encryption negotiation phase in the Sciener TTLock App version 6.4.5. The vulnerability arises because the app's communication protocol allows an attacker to send a specially crafted message that forces the app to downgrade its encryption algorithm to a weaker one. This downgrade compromises the confidentiality of the communication channel between the app and the smart lock device. Specifically, the attacker can exploit this flaw to reveal sensitive data such as the unlockKey field, which is critical for unlocking the smart lock. The attack vector is network-based (AV:N), requires no privileges (PR:N), no user interaction (UI:N), and affects the confidentiality (C:H) without impacting integrity or availability. The vulnerability is rated with a CVSS 3.1 score of 7.5 (high severity), indicating a significant risk. Although no exploits have been reported in the wild yet, the potential for unauthorized physical access through compromised smart locks is a serious concern. The lack of authentication and user interaction requirements makes this vulnerability easier to exploit remotely. The vulnerability highlights a common cryptographic weakness where fallback to weaker algorithms is permitted, enabling attackers to bypass stronger security measures. The absence of available patches at the time of publication necessitates immediate attention from users and administrators of the TTLock App to monitor for updates and implement interim protective measures.

For European organizations, the impact of CVE-2023-7005 is substantial, particularly for those relying on TTLock-enabled smart locks for physical security in offices, residential buildings, hotels, and other facilities. The exposure of the unlockKey compromises the confidentiality of access credentials, potentially allowing attackers to gain unauthorized physical entry without detection. This breach can lead to theft, espionage, or sabotage, undermining trust in smart building security systems. The vulnerability's ease of exploitation without authentication or user interaction increases the risk of widespread attacks. Additionally, organizations may face regulatory and compliance repercussions under GDPR and other data protection laws if the breach leads to unauthorized access or data loss. The risk extends to critical infrastructure and high-value targets where secure access control is paramount. The threat also challenges the adoption of IoT security best practices and may slow down smart lock deployments if not addressed promptly. Overall, the vulnerability threatens both operational security and privacy, necessitating urgent mitigation.

1. Immediate monitoring for updates from Sciener and prompt application of patches once available is critical. 2. Until patches are released, restrict network access to TTLock App communication channels using firewall rules and network segmentation to limit exposure. 3. Deploy network intrusion detection/prevention systems (IDS/IPS) configured to detect unusual downgrade negotiation attempts or anomalous traffic patterns related to TTLock communications. 4. Implement strict access controls on devices running the TTLock App, including limiting app permissions and ensuring devices are updated with the latest OS security patches. 5. Conduct regular security audits of smart lock deployments and verify the integrity of unlockKey storage and transmission. 6. Educate users and administrators about the risks of algorithm downgrade attacks and encourage vigilance for suspicious lock behavior or unauthorized access attempts. 7. Consider alternative secure access control solutions with robust cryptographic negotiation protocols if immediate patching is not feasible. 8. Collaborate with IoT security vendors and industry groups to share threat intelligence and best practices for securing smart lock ecosystems.