CVE-2025-11891 identifies a vulnerability classified under CWE-538 (Insertion of Sensitive Information into Externally-Accessible File or Directory) affecting the Shelf Planner plugin for WordPress, versions up to and including 2.7.0. The core issue is that the plugin generates log files containing sensitive information and stores them in locations accessible publicly via the web server. Because these log files are not properly protected, unauthenticated attackers can retrieve them directly without any authentication or user interaction. The sensitive information exposed could include configuration details, user data, or other operational information that could aid attackers in further attacks or data breaches. The vulnerability has a CVSS v3.1 base score of 5.3, indicating a medium severity level, with an attack vector of network (remote), low attack complexity, no privileges required, no user interaction, and impact limited to confidentiality loss only. No integrity or availability impacts are noted. No patches are currently linked, and no exploits have been observed in the wild, but the vulnerability is publicly disclosed and should be addressed promptly. The vulnerability stems from insecure logging practices within the plugin's codebase, failing to restrict access or sanitize sensitive data before logging. This issue is particularly relevant for organizations using Shelf Planner in their WordPress sites, especially those handling sensitive customer or business data.

For European organizations, the primary impact of CVE-2025-11891 is the unauthorized disclosure of sensitive information through exposed log files. This can lead to confidentiality breaches, potentially exposing customer data, internal configurations, or business-sensitive information. Such exposure can facilitate further targeted attacks, including phishing, social engineering, or exploitation of other vulnerabilities. Although the vulnerability does not affect data integrity or availability, the leakage of sensitive data can damage organizational reputation, violate data protection regulations such as GDPR, and result in compliance penalties. Organizations relying on Shelf Planner for inventory or resource planning may face operational risks if attackers gain insights into internal processes. The ease of exploitation (no authentication or user interaction required) increases the likelihood of automated scanning and data harvesting by malicious actors. The absence of known exploits in the wild currently reduces immediate risk but does not eliminate the potential for future exploitation. Overall, the vulnerability poses a moderate risk that European organizations should address promptly to maintain data confidentiality and regulatory compliance.

To mitigate CVE-2025-11891, organizations should implement the following specific measures: 1) Immediately restrict public access to the directories and files where Shelf Planner stores its log files by configuring web server access controls (e.g., using .htaccess rules, nginx configurations, or equivalent) to deny external HTTP requests to these paths. 2) Conduct an audit of existing log files to identify and securely remove any sensitive information that has been exposed. 3) Monitor web server logs for unauthorized access attempts to log file locations to detect potential reconnaissance activities. 4) Engage with the Shelf Planner vendor or community to obtain patches or updates addressing this vulnerability; if no patch is currently available, consider disabling logging features or the plugin temporarily if feasible. 5) Implement application-level logging best practices, ensuring sensitive data is not logged or is properly masked before writing to logs. 6) Harden WordPress installations by following security best practices, including least privilege principles for plugin usage and regular security assessments. 7) Educate site administrators about the risks of exposing sensitive information through logs and the importance of secure plugin configuration. These targeted actions go beyond generic advice by focusing on access control, log management, and vendor engagement specific to this vulnerability.