CVE-2025-64213 is a vulnerability identified in the StylemixThemes MasterStudy LMS Pro plugin, affecting all versions prior to 4.7.16. The issue involves the insertion of sensitive information into data sent by the application, which can be retrieved by an attacker without requiring authentication or user interaction. This means that an attacker can remotely exploit the vulnerability over the network to access confidential data embedded within communications or data transmissions handled by the LMS. The vulnerability does not impact data integrity or availability but poses a significant confidentiality risk. The CVSS 3.1 base score of 7.5 reflects a high severity due to the ease of exploitation (network vector, low attack complexity, no privileges or user interaction needed) and the high impact on confidentiality. The vulnerability likely stems from improper handling or sanitization of sensitive data before transmission, possibly exposing user credentials, personal information, or proprietary educational content. No known exploits have been reported in the wild, but the vulnerability's presence in a widely used LMS plugin makes it a critical concern for organizations relying on this software for managing learning content and user data. The lack of available patches at the time of reporting necessitates immediate attention to mitigate risk through compensating controls.

For European organizations, especially educational institutions, training providers, and enterprises using MasterStudy LMS Pro, this vulnerability could lead to unauthorized disclosure of sensitive data such as student records, personal identification information, or proprietary course materials. The breach of confidentiality could result in regulatory non-compliance under GDPR, reputational damage, and potential legal liabilities. Since the vulnerability allows remote exploitation without authentication, attackers could target vulnerable LMS instances en masse, increasing the risk of large-scale data leaks. The impact is particularly severe for organizations handling sensitive or regulated data, including universities, vocational training centers, and corporate training departments. Additionally, the exposure of sensitive data could facilitate further attacks such as phishing or social engineering against affected users. The absence of integrity or availability impact limits disruption but does not diminish the criticality of protecting confidential information in educational environments.

Organizations should immediately monitor official StylemixThemes channels for the release of security patches addressing CVE-2025-64213 and apply updates to MasterStudy LMS Pro as soon as they become available. Until patches are released, administrators should audit and restrict network access to the LMS platform, employing firewalls and intrusion detection systems to detect anomalous data exfiltration attempts. Review and minimize the amount of sensitive data transmitted by the LMS, ensuring encryption is enforced for all communications (e.g., TLS). Implement strict access controls and logging to detect unauthorized access attempts. Conduct regular security assessments and penetration testing focused on data leakage vectors within the LMS environment. Educate staff and users about the risks of data exposure and encourage vigilance for suspicious activity. If possible, isolate the LMS environment from other critical systems to contain potential breaches. Finally, prepare incident response plans specifically addressing data leakage scenarios to enable rapid containment and remediation.