CVE-2025-4543 is a critical SQL Injection vulnerability identified in LyLme Spage version 2.1, specifically within the file lylme_spage/blob/master/admin/ajax_link.php. The vulnerability arises from improper sanitization or validation of the 'sort' parameter, which is manipulated by an attacker to inject malicious SQL code. This injection flaw allows an unauthenticated remote attacker to execute arbitrary SQL commands on the backend database without requiring any user interaction or privileges. The vulnerability is remotely exploitable over the network, increasing its risk profile. Although the CVSS 4.0 base score is 6.9 (medium severity), the classification as critical by the vendor suggests that the impact could be significant depending on the database contents and deployment context. Exploitation could lead to unauthorized data disclosure, data modification, or even full compromise of the database server. The vulnerability does not require authentication or user interaction, and the attack vector is network-based, which makes it easier to exploit. No patches or mitigations have been officially released at the time of publication, and while no known exploits are reported in the wild yet, public disclosure of the exploit code increases the likelihood of active exploitation in the near future.

For European organizations using LyLme Spage 2.1, this vulnerability poses a substantial risk to the confidentiality, integrity, and availability of their data. SQL Injection can lead to unauthorized access to sensitive information such as personal data, intellectual property, or financial records, which is particularly critical under the GDPR framework that mandates strict data protection and breach notification requirements. Data integrity could be compromised by unauthorized modification or deletion of records, potentially disrupting business operations or corrupting critical datasets. Availability might also be affected if attackers execute destructive SQL commands or cause database crashes. Organizations in sectors such as finance, healthcare, government, and e-commerce are especially vulnerable due to the sensitive nature of their data and the regulatory environment in Europe. The remote and unauthenticated nature of the exploit increases the attack surface, making it imperative for affected organizations to act swiftly to prevent potential breaches and associated legal and reputational damages.

Immediate mitigation steps include implementing input validation and sanitization on the 'sort' parameter within ajax_link.php to prevent injection of malicious SQL code. Employing parameterized queries or prepared statements in the database access layer is critical to neutralize SQL Injection risks. Organizations should monitor network traffic for unusual requests targeting the vulnerable endpoint and deploy Web Application Firewalls (WAFs) with rules specifically designed to detect and block SQL Injection attempts against LyLme Spage. Since no official patch is available yet, consider temporarily disabling or restricting access to the vulnerable admin/ajax_link.php functionality, especially from untrusted networks. Conduct thorough code reviews and penetration testing focused on SQL Injection vectors in the application. Additionally, ensure that database accounts used by the application have the least privileges necessary to limit the impact of any successful injection. Regularly back up databases and verify restore procedures to mitigate data loss in case of exploitation. Finally, maintain awareness of vendor updates and apply patches promptly once released.