CVE-2025-13136 is a vulnerability classified under CWE-862 (Missing Authorization) found in the GSheetConnector For Ninja Forms plugin for WordPress, developed by westerndeal. The flaw exists in all versions up to and including 2.0.1, where the plugin fails to enforce proper capability checks on the 'njform-google-sheet-config' administrative page. This page can be accessed by users with Subscriber-level privileges or higher, allowing them to retrieve sensitive system information that should otherwise be restricted. The vulnerability does not require user interaction beyond authentication and can be exploited remotely over the network. The CVSS v3.1 base score is 4.3, indicating a medium severity with a vector of AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N, meaning the attacker needs low privileges but no user interaction, and the impact is limited to confidentiality loss without affecting integrity or availability. No patches or fixes have been published as of the vulnerability disclosure date (November 22, 2025), and no known exploits have been reported in the wild. The vulnerability could be leveraged by malicious insiders or compromised low-privilege accounts to gather information about the system configuration, potentially aiding further attacks or reconnaissance. The affected product is a WordPress plugin widely used to integrate Ninja Forms with Google Sheets, which is popular among organizations for data collection and automation.

For European organizations, this vulnerability poses a risk of unauthorized disclosure of system information to low-privilege authenticated users, such as subscribers or contributors on WordPress sites. While the direct impact is limited to confidentiality, the leaked information could facilitate further targeted attacks, including privilege escalation or data exfiltration. Organizations relying on the GSheetConnector For Ninja Forms plugin for critical data workflows may face increased risk if attackers leverage this vulnerability to map system configurations or identify additional weaknesses. The vulnerability does not affect data integrity or availability, so operational disruption is unlikely. However, the presence of unauthorized access paths undermines trust in the security posture of affected websites, which could have reputational consequences, especially for entities handling sensitive or regulated data under GDPR. The risk is heightened in environments with many users having Subscriber or higher roles, common in collaborative or content-rich websites.

To mitigate CVE-2025-13136, European organizations should immediately audit user roles and permissions on WordPress sites using the GSheetConnector For Ninja Forms plugin. Restrict Subscriber-level users from accessing the 'njform-google-sheet-config' page by implementing custom capability checks or role restrictions via WordPress hooks or security plugins. If possible, temporarily disable the GSheetConnector plugin until an official patch is released by the vendor. Monitor access logs for unusual activity targeting the configuration page. Employ web application firewalls (WAFs) to block unauthorized requests to the vulnerable endpoint. Additionally, enforce strong authentication and consider multi-factor authentication (MFA) for all WordPress accounts to reduce the risk of account compromise. Regularly update WordPress core, themes, and plugins to minimize exposure to known vulnerabilities. Engage with the plugin vendor or community to track patch availability and apply updates promptly once released.