CVE-2025-5936 is a Cross-Site Request Forgery (CSRF) vulnerability identified in the VR Calendar plugin developed by innate-images-llc for WordPress. This vulnerability affects all versions up to and including 2.4.7. The root cause is the absence or incorrect implementation of nonce validation in the syncCalendar() function. Nonces are security tokens used in WordPress to verify that requests are intentional and originate from legitimate users. Without proper nonce validation, an attacker can craft a malicious request that, when executed by an authenticated site administrator (for example, by clicking a link), triggers the calendar synchronization process without their consent. This CSRF flaw does not require the attacker to be authenticated themselves but relies on social engineering to trick an administrator into performing the action. The vulnerability impacts the integrity of the calendar data by allowing unauthorized synchronization operations, although it does not affect confidentiality or availability directly. The CVSS 3.1 base score is 4.3 (medium severity), reflecting that the attack vector is network-based, requires no privileges, but does require user interaction, and the impact is limited to integrity loss without affecting confidentiality or availability. No known exploits are currently reported in the wild, and no official patches have been linked yet. This vulnerability is categorized under CWE-352, which covers CSRF issues where state-changing requests can be forged by attackers due to missing or improper anti-CSRF tokens.

For European organizations using WordPress sites with the VR Calendar plugin, this vulnerability poses a moderate risk. An attacker could manipulate calendar data by forcing unauthorized synchronization actions, potentially disrupting event schedules or causing misinformation to be displayed. While this does not directly expose sensitive data or cause denial of service, the integrity compromise could affect business operations relying on accurate calendar information, such as event management, booking systems, or internal scheduling. Organizations in sectors like education, event planning, cultural institutions, and public services that use this plugin might experience operational disruptions or reputational damage if attackers exploit this flaw. Since exploitation requires tricking an administrator, the threat is somewhat mitigated by user awareness but remains a concern in environments with less stringent security training or where administrators frequently interact with external links.

European organizations should implement the following specific mitigations: 1) Immediately audit WordPress sites for the presence of the VR Calendar plugin and identify versions up to 2.4.7. 2) Until an official patch is released, restrict administrative access to trusted networks or VPNs to reduce exposure to CSRF attacks. 3) Educate site administrators about the risks of clicking on unsolicited links, especially those that could trigger administrative actions. 4) Employ Web Application Firewalls (WAFs) with custom rules to detect and block suspicious requests targeting the syncCalendar() function or unusual POST requests to the plugin endpoints. 5) Monitor logs for unusual calendar synchronization activities that could indicate exploitation attempts. 6) Follow the vendor's updates closely and apply patches immediately once available. 7) Consider implementing additional nonce or token validation at the application or server level if feasible, as a temporary protective measure.