CVE-2026-2431 is a reflected Cross-Site Scripting (XSS) vulnerability identified in the CM Custom Reports plugin for WordPress, versions up to and including 1.2.7. The vulnerability stems from insufficient sanitization and escaping of user-supplied input in the 'date_from' and 'date_to' URL parameters. Because these parameters are directly embedded into web pages without proper neutralization, an attacker can inject malicious JavaScript code. This code executes in the context of the victim's browser when they click a crafted link, potentially leading to session hijacking, credential theft, or unauthorized actions performed with the victim's privileges. The vulnerability does not require authentication, increasing its risk profile, but does require user interaction (clicking a malicious link). The CVSS 3.1 base score of 6.1 reflects a medium severity, with network attack vector, low attack complexity, no privileges required, user interaction required, and impacts on confidentiality and integrity but not availability. No public exploits have been reported yet, but the vulnerability is publicly disclosed and documented. The plugin is used for flexible reporting in WordPress environments, which are widely deployed globally, making this a relevant threat to many organizations using this plugin for reporting purposes.

The primary impact of this vulnerability is on the confidentiality and integrity of user data within affected WordPress sites. Successful exploitation allows attackers to execute arbitrary scripts in the context of the victim’s browser, potentially leading to session hijacking, theft of sensitive information such as cookies or credentials, and unauthorized actions performed on behalf of the user. This can result in account compromise, data leakage, and further exploitation within the affected environment. Since the vulnerability is exploitable without authentication but requires user interaction, phishing or social engineering campaigns could be used to lure victims. The scope includes any organization using the vulnerable plugin, which may include businesses, non-profits, and government websites relying on WordPress for content management and reporting. Although availability is not impacted, the breach of confidentiality and integrity can have serious reputational and operational consequences.

1. Update the CM Custom Reports plugin to the latest version once a patch is released by the vendor. Monitor official sources for updates. 2. In the absence of an immediate patch, implement Web Application Firewall (WAF) rules to detect and block malicious payloads targeting the 'date_from' and 'date_to' parameters. 3. Employ Content Security Policy (CSP) headers to restrict the execution of unauthorized scripts in the browser. 4. Educate users and administrators about the risks of clicking untrusted links, especially those containing suspicious URL parameters. 5. Review and sanitize all user inputs in custom code or plugins to prevent similar vulnerabilities. 6. Conduct regular security audits and vulnerability scans on WordPress installations and plugins. 7. Limit plugin usage to trusted sources and minimize the number of active plugins to reduce attack surface.