CVE-2023-6242 is a Cross-Site Request Forgery (CSRF) vulnerability affecting the EventON WordPress plugin, a popular virtual event calendar solution developed by ashanjay. The vulnerability exists in all versions up to and including 4.5.4 (Pro) and 2.2.7 (Free). The root cause is missing or incorrect nonce validation in the evo_eventpost_update_meta function, which is responsible for updating post metadata. Due to the lack of proper nonce checks, an attacker can craft a malicious request that, when executed by an authenticated site administrator (e.g., by clicking a link or visiting a malicious page), allows the attacker to update arbitrary post metadata without authorization. This can lead to unauthorized modifications of event data or other content managed by the plugin. The vulnerability does not require the attacker to be authenticated but does require user interaction from an administrator. The CVSS v3.1 base score is 6.5 (medium severity), reflecting the ease of exploitation (network vector, low attack complexity, no privileges required, but user interaction needed) and the impact primarily on integrity (high impact), with no confidentiality or availability impact. No known exploits are currently reported in the wild, and no official patches are linked yet. Given the plugin’s widespread use in WordPress sites for event management, this vulnerability poses a significant risk to site integrity and trustworthiness if exploited.

For European organizations using WordPress sites with the EventON plugin, this vulnerability could allow attackers to manipulate event-related content or metadata, potentially leading to misinformation, event disruption, or reputational damage. Since the attack requires tricking an administrator into performing an action, targeted phishing or social engineering campaigns could be used to exploit this flaw. The integrity of event data is critical for organizations relying on accurate scheduling and communication, such as educational institutions, conference organizers, and public service entities. Unauthorized metadata changes could also be leveraged to inject malicious content or links, indirectly facilitating further attacks or spreading misinformation. Although confidentiality and availability impacts are minimal, the integrity compromise can undermine trust in the organization’s digital presence and event management capabilities.

Organizations should immediately verify if their WordPress sites use the EventON plugin versions up to 4.5.4 (Pro) or 2.2.7 (Free). Until an official patch is released, administrators should implement the following mitigations: 1) Restrict administrative access to trusted networks or VPNs to reduce exposure to CSRF attacks. 2) Employ web application firewalls (WAFs) with custom rules to detect and block suspicious POST requests targeting the vulnerable function. 3) Educate administrators about the risks of clicking unknown or suspicious links while logged into the WordPress admin panel. 4) Monitor logs for unusual metadata update requests or patterns indicative of CSRF exploitation attempts. 5) Consider temporarily disabling or replacing the EventON plugin if feasible until a secure version is available. 6) Once patches are released, prioritize prompt updates to the plugin to restore nonce validation and eliminate the vulnerability.