CVE-2026-25364 identifies a missing authorization vulnerability in the BoldGrid Client Invoicing plugin by Sprout Invoices, specifically affecting versions up to 20.8.8. The vulnerability arises from incorrectly configured access control security levels, which fail to properly restrict user permissions within the invoicing system. This misconfiguration allows unauthorized users to perform actions that should be limited to privileged roles, such as creating, viewing, or modifying invoices without proper authorization. The plugin is commonly used within WordPress environments to manage client invoicing, making it a target for attackers seeking to manipulate financial data or gain unauthorized access to sensitive billing information. Although no known exploits have been reported in the wild, the vulnerability's nature suggests it could be exploited remotely without authentication, increasing its risk profile. The lack of a CVSS score indicates the need for an expert severity assessment, which considers the potential impact on confidentiality, integrity, and availability of invoicing data, the ease of exploitation, and the scope of affected systems. The vulnerability could lead to unauthorized invoice manipulation, financial fraud, or leakage of sensitive client information, posing significant risks to affected organizations. The issue was published in February 2026, with no patches currently linked, emphasizing the importance of monitoring vendor updates and applying fixes promptly once available.

For European organizations, this vulnerability poses a significant risk to financial data integrity and confidentiality. Unauthorized access to invoicing systems can lead to fraudulent invoice creation or modification, resulting in financial losses and reputational damage. The exposure of client billing information could violate data protection regulations such as GDPR, leading to legal and compliance consequences. Small and medium-sized enterprises (SMEs) using WordPress and the BoldGrid Client Invoicing plugin are particularly vulnerable, as they may lack robust security controls. The disruption of invoicing processes can also impact business operations and cash flow. Given the potential for remote exploitation without authentication, attackers could leverage this vulnerability to gain persistent unauthorized access, increasing the risk of extended data breaches or financial fraud. The absence of known exploits currently provides a window for proactive mitigation, but the threat remains significant due to the plugin's widespread use in European markets.

1. Monitor BoldGrid and Sprout Invoices official channels for security patches addressing CVE-2026-25364 and apply updates immediately upon release. 2. In the interim, restrict access to the Client Invoicing plugin to trusted administrative users only, minimizing exposure. 3. Conduct a thorough review of user roles and permissions within WordPress to ensure the principle of least privilege is enforced, removing unnecessary access rights. 4. Implement web application firewalls (WAF) with custom rules to detect and block unauthorized attempts to access invoicing functions. 5. Enable detailed logging and monitoring of invoicing-related activities to detect suspicious behavior promptly. 6. Educate staff on the risks associated with plugin vulnerabilities and enforce strong authentication mechanisms for administrative access. 7. Consider isolating invoicing functions on dedicated systems or environments to reduce the attack surface. 8. Regularly audit installed plugins for security posture and remove unused or unsupported plugins to minimize risk.