CVE-2026-24636 identifies a Missing Authorization vulnerability in the Sugar Calendar (Lite) WordPress plugin, versions up to and including 3.10.1. The vulnerability arises from incorrectly configured access control security levels, which fail to properly restrict user permissions when interacting with calendar features. This misconfiguration can allow an attacker to perform unauthorized actions, such as viewing, modifying, or deleting calendar events, or potentially escalating privileges within the plugin’s scope. Since Sugar Calendar (Lite) is a popular event management plugin for WordPress, widely used for scheduling and calendar functionalities on websites, this vulnerability could be exploited to compromise the confidentiality and integrity of event data. The lack of a CVSS score and absence of known exploits in the wild suggest this is a recently disclosed issue. However, the underlying cause—missing authorization checks—is a critical security flaw that can be exploited remotely without authentication or user interaction, depending on the plugin’s deployment context. The vulnerability affects all installations running the vulnerable versions, and the impact depends on the sensitivity of the calendar data and the role of the affected website. The issue was reserved and published in January 2026 by Patchstack, indicating a recognized security risk requiring prompt attention from site administrators and developers.

For European organizations, the impact of CVE-2026-24636 can be significant, especially for those relying on WordPress websites with Sugar Calendar (Lite) for event management. Unauthorized access to calendar data can lead to exposure of sensitive scheduling information, disruption of event planning, and potential manipulation of public-facing event details, damaging organizational reputation and operational continuity. In sectors such as education, government, and event management, where calendar data may include confidential or strategic information, this vulnerability could facilitate further attacks or social engineering. Additionally, exploitation could serve as a foothold for attackers to escalate privileges or pivot to other parts of the website or network. The absence of authentication requirements in some configurations increases the risk of automated exploitation. European organizations with limited patch management processes or those using outdated plugin versions are particularly vulnerable. The impact extends beyond data confidentiality to integrity and availability, as attackers could alter or delete calendar entries, disrupting business operations.

To mitigate CVE-2026-24636, organizations should first verify if their WordPress installations use Sugar Calendar (Lite) version 3.10.1 or earlier. Immediate steps include: 1) Applying official patches or updates from the vendor once released; 2) If patches are unavailable, temporarily disabling the plugin or restricting access to calendar management interfaces via web application firewalls (WAF) or IP whitelisting; 3) Reviewing and tightening user roles and permissions within WordPress to ensure least privilege principles are enforced; 4) Implementing monitoring and alerting for unusual calendar-related activities or unauthorized access attempts; 5) Conducting security audits of WordPress plugins and configurations regularly; 6) Educating site administrators on secure plugin management and the risks of outdated components; 7) Using security plugins that can detect and block unauthorized access attempts. Organizations should also maintain backups of calendar data to enable recovery in case of tampering. Proactive vulnerability scanning and penetration testing focusing on authorization controls can help identify similar issues.