CVE-2025-58921 identifies a reflected Cross-site Scripting (XSS) vulnerability in the Arevico WP Tactical Popup WordPress plugin, affecting versions up to and including 1.1. The vulnerability stems from improper neutralization of user-supplied input during the generation of web pages, allowing attackers to inject malicious JavaScript code that is reflected back to the victim's browser. This type of XSS is classified as reflected because the malicious payload is part of the request and immediately reflected in the response without proper sanitization or encoding. The CVSS 3.1 base score of 7.1 reflects a high severity due to the network attack vector (AV:N), low attack complexity (AC:L), no privileges required (PR:N), but requiring user interaction (UI:R). The impact on confidentiality is high, as attackers can steal cookies, session tokens, or other sensitive information accessible via the browser. Integrity impact is low, as the attack primarily targets client-side script execution rather than server data modification. Availability is not affected. The vulnerability does not require authentication, making it exploitable by any remote attacker who can lure users into clicking crafted URLs. Although no known exploits are currently reported in the wild, the widespread use of WordPress and the plugin's presence on public-facing websites make this a credible threat. The lack of a patch link suggests that a fix may not yet be available, emphasizing the need for interim mitigations. The vulnerability was reserved in early September 2025 and published in late October 2025, indicating recent discovery and disclosure.

For European organizations, this vulnerability poses a significant risk, especially for those relying on WordPress sites with the WP Tactical Popup plugin installed. Successful exploitation can lead to theft of user credentials, session hijacking, and unauthorized access to user accounts, potentially exposing sensitive customer or internal data. This can damage organizational reputation, lead to regulatory non-compliance (e.g., GDPR breaches), and cause financial losses. Public sector websites, e-commerce platforms, and service providers using this plugin are particularly vulnerable. The reflected XSS can also be leveraged as a stepping stone for more sophisticated attacks, including phishing campaigns and malware distribution. Given the high adoption of WordPress across Europe, the scope of affected systems is broad. The requirement for user interaction means social engineering is a key factor, increasing the risk for organizations with large user bases or external-facing portals.

Organizations should immediately inventory their WordPress installations to identify the presence of the WP Tactical Popup plugin and its version. Until an official patch is released, consider disabling or removing the plugin to eliminate the attack surface. Implement Web Application Firewalls (WAFs) with rules specifically targeting reflected XSS patterns to block malicious payloads. Employ Content Security Policy (CSP) headers to restrict the execution of unauthorized scripts in browsers. Educate users and administrators about the risks of clicking unsolicited links and encourage vigilance against phishing attempts. Monitor web server logs for suspicious requests containing script tags or unusual URL parameters. Once a patch is available, prioritize prompt application and verify the fix. Additionally, review and harden input validation and output encoding practices in custom code to prevent similar vulnerabilities.