CVE-2025-6786 is a vulnerability classified under CWE-284 (Improper Access Control) affecting the DocCheck Login plugin for WordPress, developed by antwerpes. This plugin is designed to restrict access to certain posts by requiring users to log in via DocCheck, a common authentication mechanism used in healthcare-related websites to verify professional credentials. The vulnerability exists in all versions up to and including 1.1.5. The core issue arises because the plugin redirects users to the login page only after the protected post content has already been loaded and rendered. This flawed access control mechanism allows unauthenticated attackers to bypass the intended restriction and read posts that should be password protected. The vulnerability does not require any user interaction or prior authentication, and it can be exploited remotely over the network. The CVSS v3.1 base score is 5.3 (medium severity), reflecting that the attack vector is network-based with low attack complexity, no privileges or user interaction required, and results in partial confidentiality loss (unauthorized reading of protected posts). There is no indication of integrity or availability impact. No known exploits are currently reported in the wild, and no patches have been linked yet. The vulnerability primarily affects the confidentiality of sensitive content that relies on DocCheck Login for access control, which is critical for websites handling professional or sensitive information, especially in the healthcare sector.

For European organizations, especially those in the healthcare, pharmaceutical, and medical research sectors, this vulnerability poses a significant risk to the confidentiality of sensitive information. Many European healthcare websites use DocCheck Login to restrict access to professional content, medical guidelines, or patient-related information. Unauthorized access to such content could lead to exposure of proprietary medical knowledge, professional credentials, or sensitive patient data, potentially violating GDPR and other data protection regulations. This could result in reputational damage, regulatory fines, and loss of trust among healthcare professionals and patients. Additionally, the unauthorized disclosure of protected content could facilitate further social engineering or targeted attacks against healthcare providers. Since the vulnerability does not affect integrity or availability, the primary concern remains data confidentiality. The medium severity score reflects a moderate but non-negligible threat, especially given the sensitive nature of the protected content.

To mitigate this vulnerability, European organizations using the DocCheck Login plugin should: 1) Immediately audit their WordPress installations to identify if DocCheck Login plugin versions up to 1.1.5 are in use. 2) Temporarily disable the plugin or restrict access to sensitive posts via alternative access control mechanisms until a patch is available. 3) Monitor official antwerpes and WordPress plugin repositories for security updates or patches addressing CVE-2025-6786 and apply them promptly once released. 4) Implement additional server-side access controls, such as web application firewalls (WAFs) with rules to block unauthorized access attempts to protected posts. 5) Conduct thorough logging and monitoring of access to sensitive posts to detect any anomalous or unauthorized access patterns. 6) Educate site administrators about the risks of improper access control and ensure secure configuration of authentication plugins. 7) Consider multi-factor authentication or integration with more robust identity providers to enhance access control beyond the plugin’s default mechanisms.