CVE-2026-24988 identifies a stored Cross-site Scripting (XSS) vulnerability in The Events Calendar Shortcode & Block plugin developed by Brian Hogg, affecting versions up to 3.1.1. The vulnerability is caused by improper neutralization of user-supplied input during the generation of web pages, which allows an attacker to inject malicious JavaScript code that is stored persistently within the application. When other users or administrators view the affected pages, the malicious script executes in their browsers, potentially leading to session hijacking, credential theft, unauthorized actions, or malware distribution. This vulnerability does not require authentication or user interaction beyond visiting a compromised page, increasing its risk profile. Although no public exploits have been reported yet, the nature of stored XSS makes it a critical concern for websites that rely on this plugin to display event information. The plugin is commonly used on WordPress sites to manage and display event calendars, making it a popular target for attackers seeking to compromise websites with high visitor engagement. The lack of a CVSS score indicates that the vulnerability is newly disclosed, but the technical details and typical impact of stored XSS vulnerabilities justify a high severity rating. The vulnerability was reserved on January 28, 2026, and published on February 3, 2026, with no patch links currently available, suggesting that remediation efforts are either underway or pending.

For European organizations, this vulnerability poses significant risks to the confidentiality, integrity, and availability of web applications using The Events Calendar Shortcode & Block plugin. Attackers exploiting this stored XSS flaw can execute arbitrary scripts in the context of the victim's browser, potentially stealing session cookies, redirecting users to malicious sites, or performing unauthorized actions on behalf of users. This can lead to data breaches, reputational damage, and loss of customer trust. Organizations handling sensitive user data or financial transactions are particularly vulnerable. Additionally, the persistent nature of stored XSS means that once injected, malicious scripts can affect multiple users over time, amplifying the impact. The absence of known exploits in the wild currently reduces immediate risk but does not eliminate the threat, especially as attackers often develop exploits rapidly after disclosure. European entities relying on WordPress plugins for event management, especially those with public-facing websites, should consider this vulnerability a high priority for remediation to prevent potential compromise.

1. Monitor official sources and the plugin vendor for patches or updates addressing CVE-2026-24988 and apply them promptly once available. 2. Until a patch is released, implement Web Application Firewall (WAF) rules to detect and block suspicious input patterns targeting the plugin's input fields. 3. Conduct a thorough audit of all user-generated content related to the plugin to identify and remove any malicious scripts that may have been injected. 4. Enforce strict input validation and output encoding on all data processed by the plugin, especially inputs that are rendered on web pages. 5. Limit user privileges to reduce the risk of unauthorized content injection, ensuring only trusted users can submit event data. 6. Educate site administrators and users about the risks of XSS and encourage vigilance for unusual site behavior. 7. Regularly back up website data to enable recovery in case of compromise. 8. Employ Content Security Policy (CSP) headers to restrict the execution of unauthorized scripts in browsers. 9. Use security plugins that scan for XSS vulnerabilities and malicious content on WordPress sites. 10. Review and harden overall WordPress security posture to reduce attack surface.