CVE-2026-24855 in ChurchCRM
Summary
by MITRE • 01/30/2026
ChurchCRM is an open-source church management system. Versions prior to 6.7.2 have a Stored Cross-Site Scripting (XSS) vulnerability occurs in Create Events in Church Calendar. Users with low privileges can create XSS payloads in the Description field. This payload is stored in the database, and when other users view that event (including the admin), the payload is triggered, leading to account takeover. Version 6.7.2 fixes the vulnerability.
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Analysis
by VulDB Data Team • 02/17/2026
The vulnerability identified as CVE-2026-24855 represents a critical stored cross-site scripting flaw within ChurchCRM, an open-source church management system that serves thousands of religious organizations worldwide. This security weakness exists specifically within the event creation functionality of the church calendar module, where unauthenticated malicious input can be injected into the Description field during event creation processes. The vulnerability affects all versions prior to 6.7.2, making it a widespread concern for organizations that have not yet upgraded their systems. The flaw is particularly dangerous because it allows attackers to execute malicious scripts against unsuspecting users who view the compromised calendar events, creating a persistent threat vector that can affect anyone with access to the calendar.
The technical implementation of this vulnerability stems from inadequate input sanitization and output encoding within the ChurchCRM application's event description handling mechanism. When users with low privileges create calendar events, they can inject malicious JavaScript code into the Description field without proper validation or sanitization measures. The application fails to properly escape or filter user-supplied content before storing it in the database, allowing the malicious payload to persist indefinitely. This stored data is then retrieved and displayed to other users when they view the calendar events, triggering the malicious script execution in the context of the victim's browser session. The vulnerability directly maps to CWE-79, which describes Cross-Site Scripting flaws, and represents a classic case of stored XSS where the malicious content is permanently stored on the server rather than being reflected in a single request.
The operational impact of this vulnerability extends far beyond simple data corruption or display issues, as it provides attackers with a pathway for account takeover and persistent access to church management systems. When other users, including administrators, view the compromised calendar events, their browsers execute the injected JavaScript code, potentially allowing attackers to steal session cookies, credentials, or perform actions on behalf of authenticated users. This creates a significant risk for church organizations that rely on ChurchCRM for sensitive data management, including member information, financial records, and organizational communications. The vulnerability's impact is amplified by the fact that administrators are likely to view calendar events regularly, making them frequent targets for exploitation. According to ATT&CK framework, this vulnerability aligns with T1531, which covers "Account Access Removal" and T1078, "Valid Accounts," as it enables unauthorized access to privileged accounts through session hijacking techniques.
Organizations affected by this vulnerability should immediately implement several mitigation strategies to protect their systems and data. The primary and most effective mitigation is upgrading to ChurchCRM version 6.7.2 or later, which includes proper input validation and output encoding mechanisms that prevent malicious payloads from being stored or executed. Additionally, administrators should implement content security policies that restrict script execution within the application interface, though this serves as a secondary defense mechanism. Regular security audits of user input fields, particularly those that support rich text or HTML content, should be conducted to identify potential injection points. Network monitoring should be enhanced to detect unusual patterns in calendar event creation or access, and user access controls should be reviewed to minimize the impact of potential compromises. The vulnerability demonstrates the critical importance of proper input validation and output encoding in web applications, particularly those handling sensitive organizational data, and serves as a reminder that even open-source applications require regular security updates and monitoring to maintain robust protection against evolving threats.